A linguistic universal is a pattern that occurs systematically across natural languages, potentially true for all of them. For example, All languages have nouns and verbs, or If a language is spoken, it has consonants and vowels. Research in this area of linguistics is closely tied to the study of linguistic typology, and intends to reveal generalizations across languages, likely tied to cognition, perception, or other abilities of the mind. The field originates from discussions influenced by Noam Chomsky's proposal of a Universal Grammar, but was largely pioneered by the linguist Joseph Greenberg, who derived a set of forty-five basic universals, mostly dealing with syntax, from a study of some thirty languages.

Though there has been significant research into linguistic universals, in more recent time some linguists, including Nicolas Evans and Stephen C. Levinson, have argued against the existence of absolute linguistic universals that are shared across all languages. These linguists cite problems such as ethnocentrism amongst cognitive scientists, and thus linguists, as well as insufficient research into all of the world's languages in discussions related to linguistic universals, instead promoting these similarities as simply strong tendencies.