\ ˈī How to pronounce ai (audio) , ˈä-ˌē, ä-ˈē\
plural ais

Definition of ai

 (Entry 1 of 2)

: three-toed sloth A sloth is a slow-moving arboreal (tree-dwelling) mammal and the name ai was given to this creature because of its high-pitched screech.— Al Perkins Three-toed sloth is a common crossword puzzle clue for the word "ai."— Marty Noble

Definition of AI (Entry 2 of 2)

1 ad interim
2 airborne intercept
3 air interception
4 artificial insemination
5 artificial intelligence

First Known Use of ai


1625, in the meaning defined above

History and Etymology for ai


borrowed from Portuguese "sloth (the animal)," borrowed from Tupi aɨ́

Note: The Tupi form is based on that given by Aryon Rodrigues in "Contribuição para a etimologia dos brasileirismos," Revista Portuguesa de Filologia, vol. 9, I-II (1958-59), p. 14. The word can be found with various spellings in a number of early sources: André Thevet, Les singularitez de la France Antarctique, 1558 (Haü, Haüthi); Jean de Léry, Histoire d'un voyage faict en la terre du Bresil, 1578 (Hay); letter of José de Anchieta, 1560, in Serafim Leite, editor, Cartas dos primeiros Jesuítas do Brasil, vol. 3 [1958], p. 222, cited in Antônio Geraldo da Cunha, Dicionário histórico das palavras portuguesas de origem tupi, São Paulo, 1978 ("Est aliud animal quod Indi aig, nos propter nimiam tarditatem pigritiam dicimus" - "There is another animal that the Indians call aig, that we call on account of its excessive slowness the sloth"); Gabriel Soares de Sousa, Tratado descritivo do Brasil, 1587 (ahy).

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Ahura Mazda







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Last Updated

17 Sep 2019

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The first known use of ai was in 1625

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Medical Definition of AI

artificial insemination

More from Merriam-Webster on ai

Rhyming Dictionary: Words that rhyme with ai

Nglish: Translation of ai for Spanish Speakers

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