Editing Consonant mutation (section)

== Similar sound changes ==
Initial consonant mutation must not be confused with [[sandhi]], which can refer to word-initial alternations triggered by their [[phonology|phonological]] environment, unlike mutations, which are triggered by their [[morphosyntactic]] environment. Some examples of word-initial sandhi are listed below.
*[[Spanish language|Spanish]]: {{IPA|[b, d, ɡ]}}, occurring after [[nasal consonant|nasals]] and pause, alternate with {{IPA|[β, ð, ɣ]}}, occurring after [[vowel]]s and [[liquid consonant]]s. Example: un ['''b''']arco 'a boat', mi ['''β''']arco 'my boat'. This also occurs in [[Hebrew language|Hebrew]] (as [[Begadkefat|begedkefet]], an [[Acronyms in Hebrew|acronym]] for the consonants this affects), [[Aramaic language|Aramaic]], and [[Tamil language|Tamil]].
*Scottish Gaelic: in some dialects, stops in stressed syllables are voiced after nasals, e.g. cat {{IPA|['''kʰ'''aht]}} 'a cat', an cat {{IPA|[əŋ '''ɡ'''aht]}} 'the cat'.

Sandhi effects like these (or other phonological processes) are usually the historical origin of morphosyntactically triggered mutation. For example, English fricative mutation (specifically, voicing) in words such as ''house'' [haus], plural ''houses'' [hauzɪz], and the verb ''to house'' [hauz] originates in an [[allophone|allophonic]] alternation of [[Old English language|Old English]], where a voiced fricative occurred between vowels (or before voiced consonants), and a voiceless one occurred initially or finally, and also when adjacent to voiceless consonants. Old English infinitives ended in ''-(i)an'' and plural nouns (of Class One nouns) ended in ''-as''. Thus, ''hūs'' 'a house' had {{IPA|[s]}}, and ''hūsian'' 'house (verb)' had {{IPA|[z]}}; however,  the plural of ''hūs'' was ''hūs'', being a neuter noun of the strong a-stem class. During the Middle English period, ''hous''~''hus'', as part of the loss of gender and erosion of endings, developed plural variation, retaining ''hous'' [hu:s], the dative plural ''housen'' [hu:zən], which became extended to a general plural, and over time taking on the ''es'' plural from Old English Class 1 nouns, thus ''houses'' [hu:zəz].  After most endings were lost in English, and the contrast between voiced and voiceless fricatives partly phonemicized (largely due to the influx of [[French language|French]] loanwords), the alternation was morphologized.