Definition of is

 (Entry 1 of 4)

present tense third-person singular of be

dialectal present tense first-person and third-person singular of be

dialectal present tense plural of be

Definition of is (Entry 2 of 4)

island; isle

Definition of IS (Entry 3 of 4)

information system
variants: or iso-

Definition of is- (Entry 4 of 4)

1 : equal : homogeneous : uniform isentropic
2 : isomeric isocyanate
3 : for or from different individuals of the same species isoagglutinin

History and Etymology for is

Middle English, from Old English; akin to Old High German ist is (from sīn to be), Latin est (from esse to be), Greek esti (from einai to be)

Combining form

Late Latin, from Greek, from isos equal

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Cite this Entry

“Is.” Dictionary, Merriam-Webster, Accessed 6 Aug. 2020.

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Kids Definition of is

present tense third person singular of be

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Thesaurus: All synonyms and antonyms for is

Rhyming Dictionary: Words that rhyme with is

Spanish Central: Translation of is

Nglish: Translation of is for Spanish Speakers

Britannica English: Translation of is for Arabic Speakers

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