Editing Esperanto (section)

=== Vocabulary ===
{{Main|Esperanto vocabulary}}
{{Wiktionary category|category=Esperanto language}}

The core vocabulary of Esperanto was defined by {{lang|eo|Unua Libro}}, published by Zamenhof in 1887. This book listed 917 roots; these could be expanded into tens of thousands of words using prefixes, suffixes, and compounding. In 1894, Zamenhof published the first Esperanto [[dictionary]], {{ill|Universala Vortaro|eo}}, which had a larger set of roots. The rules of the language allowed speakers to borrow new roots as needed; it was recommended, however, that speakers use most international forms and then derive related meanings from these.

Since then, many words have been borrowed, primarily (but not solely) from the European languages. Not all proposed borrowings become widespread, but many do, especially [[technical terminology|technical]] and [[science|scientific]] terms. Terms for everyday use, on the other hand, are more likely to be derived from existing roots; {{lang|eo|komputilo}} "computer", for instance, is formed from the verb {{lang|eo|komputi}} "compute" and the suffix {{lang|eo|-ilo}} "tool". Words are also [[calque]]d; that is, words acquire new meanings based on usage in other languages. For example, the word {{lang|eo|muso}} "mouse" has acquired the meaning of a [[mouse (computing)|computer mouse]] from its usage in many languages (English ''mouse'', French ''souris'', Dutch ''muis'', Spanish ''ratón'', etc.). Esperanto speakers often debate about whether a particular borrowing is justified or whether meaning can be expressed by deriving from or extending the meaning of existing words.

Some compounds and formed words in Esperanto are not entirely straightforward; for example, {{lang|eo|eldoni}}, literally "give out", means "publish", paralleling the usage of certain European languages (such as German {{lang|de|herausgeben}}, Dutch {{lang|nl|uitgeven}}, Russian {{lang|ru|издать izdat'}}). In addition, [[Esperanto words with the ad hoc suffix -um|the suffix ''-um-'']] has no defined meaning; words using the suffix must be learned separately (such as {{lang|eo|dekstren}} "to the right" and {{lang|eo|dekstrumen}} "clockwise").

There are not many idiomatic or slang words in Esperanto, as these forms of speech tend to make international communication difficult—working against Esperanto's main goal.{{Citation needed|date=August 2020}}

Instead of derivations of Esperanto roots, new roots are taken from European languages in the endeavor to create an international language.<ref name="piron1989">{{lang|eo|La Bona Lingvo}}, [[Claude Piron]]. Vienna: {{lang|eo|Pro Esperanto}}, 1989. {{lang|eo|La lingvo volas eleganti, ne elefanti.}} "The language wants to be elegant, not elephantine."</ref>