Zero copula is a linguistic phenomenon whereby the subject is joined to the predicate without overt marking of this relationship (like the copula "to be" in English). One can distinguish languages that simply do not have a copula and languages that have a copula that is optional in some contexts.

Many languages exhibit this in some contexts, including Assamese, Bengali, Kannada, Malay/Indonesian, Turkish, Tamil, Telugu, Malayalam, Hindi, Guarani, Kazakh, Turkmen, Japanese, Ukrainian, Russian, Belarusian, Tatar, Azerbaijani, Swahili, Hungarian, Hebrew, Arabic, Berber, Ganda, Hawaiian, Sinhala, Irish, Welsh, Nahuatl, Maori, Mongolian, Greenlandic, Lithuanian, Latvian, Polish, Slovakian, Quechua and American Sign Language.

Dropping the copula is also found, to a lesser extent, in English and many other languages, used most frequently in rhetoric, casual speech, non-standard varieties, and headlinese, the writing style used in newspaper headlines. Sometimes, these omissions cause unintended syntactic ambiguity.