Editing English plurals (section)

====Irregular plurals from foreign languages====
=====Irregular plurals from Latin and Greek=====
{{See also|Plural form of words ending in -us}}
English has borrowed a great many words from [[Classical Latin]] and [[Ancient Greek grammar|Classical Greek]]. Classical Latin has a very complex system of endings in which there are five categories or [[Latin declension|declensions]] of nouns, adjectives, and pronouns (some with sub-categories). Usually, in borrowing words from Latin, the endings of the nominative are used: nouns whose nominative singular ends in ''-a'' ([[first declension]]) have plurals in ''-ae'' (''anima'', ''animae''); nouns whose nominative singular ends in ''-um'' ([[second declension]] neuter) have plurals in ''-a'' (''stadium'', ''stadia''; ''datum'', ''data''). (For a full treatment, see [[Latin declensions]].)<!-- Not really an example as it's borrowed as a whole phrase: Sometimes forms other than the [[nominative]] are seen: ''in partibus infidelium'' ("in the lands of the heathens") where ''partibus'' is an [[ablative]] plural and ''infidelium'' is a [[genitive]] plural. -->

Classical Greek has a simpler system, but still more complicated than that of English. Most loan words from Greek in English are from [[Attic Greek]] (the Athenian Greek of [[Plato]], [[Aristotle]], and other great writers), not [[Demotic Greek]], [[Koine Greek|Koine (Biblical) Greek]], or [[Modern Greek]]. This is because Attic Greek is what is taught in classes in Greek in Western Europe, and therefore was the Greek that the word borrowers knew.

======Anglicisation======
The general trend with [[loanwords]] is toward what is called ''Anglicisation'' or ''naturalisation'', that is, the re-formation of the word and its inflections as normal English words. Many nouns have settled on, or acquired a modern form from the original (usually Latin). Other nouns have become Anglicised, taking on the normal "s" ending. In some cases, both forms are still competing.

The choice of a form can often depend on context: for a scholar, the plural of ''[[wikt:appendix|appendix]]'' is ''appendices'' (following the original language); for some physicians, the plural of ''appendix'' is ''appendixes''. Likewise, a [[radio]] or [[radar]] [[engineer]] works with ''antennas'', but an [[entomologist]] deals with ''antennae''. The choice of form can also depend on the level of discourse: traditional Latin plurals are found more often in academic and scientific contexts, whereas in daily speech the Anglicised forms are more common. In the following table, the Latin plurals are listed, together with the Anglicised forms when these are more common.

Different paradigms of Latin pronunciation can lead to confusion as to the number or gender of the noun in question. As traditionally used in English, including scientific, medical, and legal contexts, Latin nouns retain the classical inflection with regard to spelling; however, those inflections use an [[Traditional English pronunciation of Latin|Anglicised pronunciation]]: the entomologist pronounces ''antennae'' as {{IPA|/ænˈtɛni/}}. This may cause confusion for those familiar with the Classical Latin pronunciation {{IPA|/ænˈtɛnaɪ/}}. The words ''alumni'' (masculine plural) and ''alumnae'' (feminine plural) are notorious in this regard, as ''alumni'' in Anglicised pronunciation sounds the same as ''alumnae'' in [[Latin spelling and pronunciation#Ecclesiastical pronunciation|Classical Latin pronunciation]], and [[vice versa]].

Because many of these plurals do not end in ''-s'', some of them have been reinterpreted as singular forms: particularly the words ''datum'' and ''medium'' (as in a "medium of communication"), where the original plurals ''data'' and ''media'' are now, in many contexts, used by some as singular mass nouns: "The media is biased"; "This data shows us that&nbsp;..." (although a number of scientists, especially of British origin, still say "These data show us that&nbsp;..."). See [[#datum data|below]] for more information. Similarly, words such as ''criteria'' and ''phenomena'' are used as singular by some speakers, although this is still considered incorrect in standard usage (see [[#phenomenon|below]]).

Final ''-a'' becomes ''-ae'' (also ''-æ''{{citation needed|date=August 2017}}), or just adds ''-s'':
{{block indent|{{wikitable
|alumna||alumnae
|-
|antenna||antennae
|-
|aurora||aurorae/auroras
|-
|formula||formulae/formulas
|-
|encyclopaedia (or encyclopædia) / encyclopedia||| encyclopaedias / encyclopedias (encyclopaediae and encyclopediae are rare)
|-
|larva||larvae
|-
|pupa||pupae/pupas
}}}}
Scientific abbreviations for words of Latin origin ending in ''-a'', such as ''SN'' for ''supernova'', can form a plural by adding ''-e'', as ''SNe'' for ''supernovae''.

Final ''-ex'' or ''-ix'' becomes ''-ices'' (pronounced {{IPA|/ᵻsiːz/}}), or just adds ''-es'':
{{block indent|{{wikitable
|index||indices||{{IPA|/ˈɪndᵻsiːz/}}|| or indexes
|-
|matrix||matrices||{{IPA|/ˈmeɪtrᵻsiːz/}}
|-
|vertex||vertices||{{IPA|/ˈvɜːrtᵻsiːz/}}
}}}}

Final ''-is'' becomes ''-es'' (pronounced {{IPA|/iːz/}}) or ''-ises/-ides'':
{{block indent|{{wikitable
|axis||axes||{{IPA|/ˈæksiːz/}}
|-
|genesis||geneses||{{IPA|/dʒɛn.ə.siːz/}}
|-
|nemesis||nemeses||{{IPA|/ˈnɛməsiːz/}}
|-
|crisis||crises||{{IPA|/ˈkraɪsiːz/}}
|-
|testis||testes||{{IPA|/ˈtɛstiːz/}}
|-
|thesis||theses||{{IPA|/ˈθiːsiːz/}}
|-
|parenthesis||parentheses||{{IPA|/pəˈrɛnθəsiːz/}}
|-
|clitoris||clitorises/clitorides||{{IPA|/ˈklɪtərɪsiz/}}
}}}}
Except for words derived from Greek {{Lang|grc-Latn|polis}}, which become {{Lang|grc-Latn|poleis}} (pronounced {{IPA|/iːs/}} or {{IPA|/iːz/}}):
{{block indent|{{wikitable
|acropolis||acropoleis||{{IPA|/æˈkropoliːs/}}
}}}}

(Some of these are Greek rather than Latin words, but the method of plural formation in English is the same.) Some people treat ''process'' as if it belonged to this class, pronouncing ''processes'' {{IPA|/ˈprɒsᵻsiːz/}} instead of standard {{IPA|/ˈprɒsɛsᵻz/}}. Since the word comes from Latin {{Lang|la|processus}}, whose plural in the [[Latin declension#Fourth declension (u)|fourth declension]] is {{Lang|la|processūs}} with a long ''u'', this pronunciation is by [[Analogy#Linguistics|analogy]], not etymology. ''Axes'' {{IPA|(/ˈæksiːz/)}}, the plural of ''axis'', is pronounced differently from ''axes'' {{IPA|(/ˈæksᵻz/)}}, the plural of ''ax(e)''.

Final ''-ies'' remains unchanged:
{{block indent|{{wikitable
|series||series
|-
|species||species
}}}}
''Specie'' for a singular of ''species'' is considered nonstandard. It is standard meaning the form of money, where it derives from the Latin singular ablative in the phrase ''in specie''.

{{Anchor|datum_data}}Final ''-um'' becomes ''-a'', or just adds ''-s'':
{{block indent|{{wikitable|style="vertical-align:top"
|-
|addendum||addenda/addendums
|-
|agendum (obsolete, not listed in most dictionaries)||agenda means a "list of items of business at a meeting" and has the plural ''agendas''.
|-
|corrigendum||corrigenda
|-
|curriculum||curricula/curriculums
|-
|datum||data (now usually treated as a singular mass noun in both informal and educated usage, but usage in scientific publications shows a strong American/British divide; American usage generally prefers to treat ''data'' as a singular in all contexts, including in serious and academic publishing.<ref>"Sometimes scientists think of data as plural, as in ''These data do not support the conclusions.'' But more often scientists and researchers think of data as a '''''singular mass entity like information''''', and most people now follow this in general usage."<!-- Emphasis added or in original? --> {{cite web |url=http://www.bartleby.com/61/51/D0035100.html |title=Data. The American Heritage® Dictionary of the English Language: Fourth Edition. 2000. |access-date=2007-10-20 |url-status=dead |archive-url=https://web.archive.org/web/20071104104416/http://www.bartleby.com/61/51/D0035100.html |archive-date=4 November 2007}}</ref><ref>{{cite news |last1=O'Neill |first1=Dan |title=Data is/data are |department=Community Science Forum |url=https://newspaperarchive.com/fairbanks-daily-news-miner-sep-22-1979-p-22/ |url-access=subscription |work=Fairbanks Daily News-Miner |volume=77 |issue=224 |date=September 22, 1979 |page=B-2 |via=[[Newspaper Archive]] |quote=[O]f the 136 distinguished consultants on usage polled for the 1975 Harper Dictionary of Contemporary Usage, 49 per cent responded that they use 'The data is...' in writing. And, in casual speech, 65 per cent use data as singular. Those who defend 'The data is...' often point to the fact that agenda is also, strictly, a plural, but is nearly always regarded as a single list and takes a singular verb. You'll probably never hear anyone ask: 'Are the agenda interesting?'}}</ref><ref>{{cite web|url=http://www.iq.harvard.edu/blog/sss/archives/2007/09/how_many_data_a.shtml|title=Summary of dictionary sources and scholarly usage|website=Harvard University|access-date=6 April 2018|archive-url=https://web.archive.org/web/20080515213104/http://www.iq.harvard.edu/blog/sss/archives/2007/09/how_many_data_a.shtml|archive-date=15 May 2008|url-status=dead}}</ref> British usage now widely accepts treating ''data'' as singular in standard English,<ref>''New Oxford Dictionary of English'', 1999</ref> including educated everyday usage<ref>"...&nbsp;in educated everyday usage as represented by the ''Guardian'' newspaper, it is nowadays most often used as a singular." {{cite web|url=http://www.eisu2.bham.ac.uk/johnstf/revis006.htm |author=Tim Johns |title=Data: singular or plural? |website=Tim Johns EAP Page |access-date=2014-06-27 |url-status=dead |archive-url=https://web.archive.org/web/20090211165815/http://eisu2.bham.ac.uk/johnstf/revis006.htm |archive-date=11 February 2009 }}</ref> at least in non-scientific use.<ref>{{cite web|url=https://www.oxforddictionaries.com/|archive-url=https://web.archive.org/web/20010516042450/http://www.oxforddictionaries.com/|url-status=dead|archive-date=16 May 2001|title=Oxford Dictionaries |website=Oxford Dictionaries|access-date=6 April 2018}}</ref>{{nonspecific|date=June 2022}} British scientific publishing usually still prefers treating ''data'' as a plural.<ref>{{cite web|url=http://www.eisu2.bham.ac.uk/johnstf/revis006.htm |author=Tim Johns |title=Data: singular or plural? |website=Tim Johns EAP Page |access-date=2014-06-27 |url-status=dead |archive-url=https://web.archive.org/web/20090211165815/http://eisu2.bham.ac.uk/johnstf/revis006.htm |archive-date=11 February 2009 }}</ref> Some British university style guides recommend using ''data'' for both the singular and the plural use<ref>[http://www.nottingham.ac.uk/public-affairs/uon-style-book/singular-plural.htm UoN "Style Book – Singular or plural"]. Media and Public Relations Office, University of Nottingham. {{webarchive |url=https://web.archive.org/web/20100726063013/http://www.nottingham.ac.uk/public-affairs/uon-style-book/singular-plural.htm |date=26 July 2010 }}</ref> and some recommend treating it only as a singular in connection with computers.<ref>{{cite web|url=http://openlearn.open.ac.uk/mod/resource/view.php?id=182902|title=Open Learning |publisher=Open University|access-date=6 April 2018}}</ref>)

In engineering, drafting, surveying, and geodesy, and in [[weight and balance#Terms|weight and balance]] calculations for aircraft, a [[datum (geodesy)|datum]] (plural datums or data) is a reference point, surface, or axis on an object or the Earth's surface against which measurements are made.
|-
|forum||fora/forums (''fora'' is rare and might only be used to refer to more than one original Roman forum)
|-
|medium||media (in [[communication system]]s and [[digital computer]]s; this is now often treated as a singular mass noun); mediums (spiritualists, or items of medium size)
|-
|memorandum||memoranda/memorandums
|-
|millennium||millennia/millenniums
|-
|ovum||ova
|-
|referendum||referendums (often taken to mean plebiscites, and referenda as the propositions voted on. It is often argued that ''referenda'' is incorrect because it is a Latin [[gerund]], which did not have a plural form, while the "propositions voted on" is more like a [[gerundive]], which could be pluralised.)
|-
|spectrum||spectra (as in [[power spectrum]] in [[electrical engineering]])
|-
|stadium||stadia/stadiums (the latter is far more common)
|-
|stratum||strata
}}}}

{{Anchor|plural_for_suffix_us}}Final ''-us'' becomes ''-i'' ([[second declension]], {{IPA|[aɪ]}}) or ''-era'' or ''-ora'' ([[third declension]]), or just adds ''-es'' (especially for [[fourth declension]] words, where the Latin plural was similar to the singular):
{{block indent|{{wikitable|style="vertical-align:top"
|alumnus||alumni
|-
|cactus||cactuses/cacti (in [[Arizona]] many people avoid either choice with ''cactus'' as both singular and plural){{Citation needed|date=February 2021}}
|-
|campus||campuses (The Latinate plural form ''campi'' is sometimes used, particularly with respect to colleges or universities; however, it is sometimes frowned upon. By contrast, the common plural form ''campuses'' is universally accepted.){{Citation needed|date=February 2021}}
|-
|corpus||corpora/corpuses
|-
|census||censuses
|-
|focus||foci/focuses
|-
|fungus||fungi
|-
|genus||genera
|-
|hippopotamus||hippopotamuses/hippopotami
|-
|octopus||octopuses (''octopi'' also occurs, although it is strictly speaking unfounded<ref>{{cite web|url=http://www.oxforddictionaries.com/us/words/what-are-the-plurals-of-octopus-hippopotamus-syllabus|archive-url=https://web.archive.org/web/20131101044550/http://www.oxforddictionaries.com/us/words/what-are-the-plurals-of-octopus-hippopotamus-syllabus|url-status=dead|archive-date=1 November 2013|title=What are the plurals of 'octopus', 'h... - Oxford Dictionaries|website=Oxford Dictionaries - English|access-date=6 April 2018}}</ref> because it is not a Latin noun of the second declension, but rather a Latinized form of Greek {{Lang|grc|ὀκτώπους|size=90%}} [{{Lang|grc-Latn|oktṓpous}}, "eight-foot"]. The theoretically correct form ''octopodes'' is rarely used.)
|-
|platypus||platypuses (same as ''octopus'': ''platypi'' occurs but is etymologically incorrect, and ''platypodes'', while technically correct, is even rarer than ''octopodes'')
|-
|prospectus||prospectuses (plural ''prospectus'' is rare although correct in Latin)
|-
|radius||radii
|-
|succubus||succubi (the word ''omnibus'' is similar in form but is originally dative plural, so cannot be pluralised to *''omnibi'': see ''[[The Motor Bus]]'')
|-
|stylus||styli/styluses
|-
|syllabus||syllabi/syllabuses
|-
|terminus||termini/terminuses
|-
|uterus||uteri/uteruses
|-
|viscus||viscera
|-
|virus||viruses (see {{format link|Plural form of words ending in -us#Virus}})
}}}}

Final ''-us'' remains unchanged in the plural (fourth declension—the plural has a long ū to differentiate it from the singular short u):
{{block indent|{{wikitable|style="vertical-align:top"
|meatus||meatus (but usually ''meatuses'')
|-
|status||status (but usually ''statuses'')
|-
|apparatus||apparatus (but usually ''apparatuses'')
}}}}

Colloquial usages based in a humorous fashion on the second declension include ''Elvii'' (better Latin would be ''Elvēs'' or Elvidēs) to refer to multiple [[Elvis impersonators]], and ''Loti'', used by [[wikt:petrolhead|petrolheads]] to refer to [[Lotus Cars|Lotus]] automobiles in the plural.

Some Greek plurals are preserved in English (''cf.'' [[English words of Greek origin#Inflectional endings and plurals|Plurals of words of Greek origin]]):

{{Anchor|phenomenon}}Final ''-on'' becomes ''-a'':
{{block indent|{{wikitable
|automaton||automata/automatons
|-
|criterion||criteria/criterions (the latter form is rare)
|-
|phenomenon||phenomena/phenomenons (the latter form is common, though sometimes proscribed)
|-
|polyhedron||polyhedra/polyhedrons
}}}}

Final ''-as'' in one case changes to ''-antes'':
{{block indent|{{wikitable
|Atlas||Atlantes (statues of the Titan); but
|-
|atlas||atlases (map collections)
}}}}

Final ''-ma'' in nouns of Greek origin can become ''-mata'', although ''-s'' is usually also acceptable, and in many cases more common.
{{block indent|{{wikitable
|stigma||stigmata/stigmas
|-
|stoma||stomata/stomas
|-
|schema||schemata/schemas
|-
|dogma||dogmata/dogmas
|-
|lemma||lemmata/lemmas
|-
|magma||magmata/magmas
|-
|anathema||anathemata/anathemas
|-
|enema
|enemata/enemas
}}}}
Such ''-ata'' plurals also occur in Latin words borrowed from Greek, e.g. ''poemata''. The ''a'' is short in both languages.

===== Irregular plurals from other languages =====
Some nouns of [[French language|French]] origin add an ''-x'', which may be silent or pronounced {{IPA|/z/}}:
{{block indent|{{wikitable
|beau||beaux or beaus
|-
|bureau||bureaux or bureaus
|-
|château||châteaux or châteaus
|-
|milieu||milieux or milieus
|-
|tableau||tableaux or tableaus
}}}}

See also {{slink||French compounds}} below.

Italian nouns, notably technical terms in music and art, often retain the Italian plurals:
{{block indent|{{wikitable
|-
| cello||celli
|-
| timpano||timpani
}}}}

Foreign terms may take native plural forms, especially when the user is addressing an audience familiar with the language. In such cases, the conventionally formed English plural may sound awkward or be confusing.

Nouns of [[Slavic languages|Slavic]] origin add ''-a'' or ''-i'' according to native rules, or just ''-s'':
{{block indent|{{wikitable
|-
| kniazhestvo||kniazhestva / kniazhestvos
|-
| kobzar||kobzari / kobzars
|-
| oblast||oblasti / oblasts
}}}}

Nouns of [[Hebrew language|Hebrew]] origin add ''-im'' or ''-ot'' (generally m/f) according to native rules, or just ''-s'':
{{block indent|{{wikitable
|cherub||cherubim / cherubs
|-
|seraph||seraphim / seraphs (The Hebrew singular is ''saraph''. ''Seraph'' is a back-formation from ''seraphim''. The form ''seraphims'' occurs in the King James Version.)
|-
|matzah||matzot / matzahs
|-
|kibbutz||kibbutzim / kibbutzes
|-
}}}}
''-ot'' is pronounced ''os'' (with unvoiced ''s'') in the [[Ashkenazi]] dialect.

Many nouns of [[Japanese language|Japanese]] origin have no plural form and do not change:
{{block indent|{{wikitable
|bentō||bentō
|-
|otaku||otaku
|-
|Pokémon||Pokémon
|-
|samurai||samurai
}}}}
Other nouns such as ''kimonos'', ''ninjas'', ''futons'', and ''tsunamis'' are more often seen with a regular English plural.

In [[New Zealand English]], nouns of [[Māori language|Māori]] origin can either take an ''-s'' or have no separate plural form. Words more connected to Māori culture and used in that context tend to retain the same form, while names of flora and fauna may or may not take an ''-s'', depending on context. Many regard omission as more correct:
{{block indent|{{wikitable
|kiwi<ref group="b">When referring to the bird, ''kiwi'' may or may not take an ''-s''; when used as an informal term for a New Zealander, it always takes an ''-s''.</ref>||kiwi/kiwis
|-
|kowhai||kowhai/kowhais
|-
|Māori<ref group="b">''Māori'', when referring to a person of that ethnicity, does not usually take an ''-s''. Many speakers avoid the use of ''Māori'' as a noun, and instead use it only as an adjective.</ref>||Māori/(''occasionally'' Māoris)
|-
|marae||marae
|-
|tui||tuis/tui
|-
|waka (canoe)|waka||waka
}}}}

'''Notes:'''
{{Reflist| group="b"|close}}

Some words borrowed from [[Inuktitut]] and related languages spoken by the [[Inuit]] in Canada, Greenland and Alaska, retain the original plurals. The word ''Inuit'' itself is the plural form. Canadian English also borrows Inuktitut singular ''Inuk'',<ref>{{cite web|url=https://www.btb.termiumplus.gc.ca/tpv2guides/guides/wrtps/index-eng.html?lang=eng&lettr=indx_catlog_i&page=91V1uxvxfEc4.html|title=Inuit, Inuk (Linguistic recommendation from the Translation Bureau)|publisher=Government of Canada, Public Works and Government Services Canada, Translation Bureau|date=8 October 2009|access-date=6 April 2018}}</ref> which is uncommon in English outside Canada.
{{block indent|{{wikitable
|Inuk (uncommon)||Inuit
|-
|inukshuk||inukshuit (rare)
|-
| Iqalummiuq || Iqalummiut ("inhabitants of [[Iqaluit]]")
|-
| Nunavimmiuq || Nunavimmiut ("inhabitants of [[Nunavik]]")
|-
| Nunavummiuq || Nunavummiut ("inhabitants of [[Nunavut]]")
}}}}

Nouns from languages other than the above generally form plurals as if they were native English words:
{{block indent|{{wikitable
|canoe||canoes
|-
|cwm||cwms||"Welsh valley"; the [[Welsh language|Welsh]] plural is {{lang|cy|cymoedd}}
|-
|goulash||goulashes||the Hungarian plural of {{lang|hu|gulyás}} is {{lang|hu|gulyások}}
|-
|igloo||igloos||the Inuktitut plural of {{lang|iu|ᐃᒡᓗ}} {{lang|iu-Latn|iglu}} is {{lang|iu|ᐃᒡᓗᐃᑦ}} {{lang|iu-Latn|igluit}}
|-
|kangaroo||kangaroos
|-
|kayak||kayaks||the Inuktitut plural of {{lang|iu|ᖃᔭᖅ}} {{lang|iu-Latn|qajaq}} is {{lang|iu|ᖃᔭᐃᑦ}} {{lang|iu-Latn|qajait}}
|-
|kindergarten||kindergartens||the German plural is {{lang|de|Kindergärten}}
|-
|ninja||ninja/ninjas||Japanese does not have plural forms
|-
|pizza||pizzas||the Italian plural is {{lang|it|pizze}}
|-
|sauna||saunas||the Finnish plural is {{lang|fi|saunat}}
}}}}