they (thā), plural pronoun; possessive Theirs; objective Them. [Icel. þeir they, properly nom. pl. masc. of sā, sū, þat, a demonstrative pronoun, akin to the English definite article, AS. sē, seó, ðaet, nom. pl. ðā. See That.] The plural of he, she, or it. They is never used adjectively, but always as a pronoun proper, and sometimes refers to persons without an antecedent expressed.

Jolif and glad they went unto here [their] rest
And casten hem [them] full early for to sail. Chaucer.

They of Italy salute you. Heb. xiii. 24.

Blessed are they which do hunger and thirst after righteousness. Matt. v. 6.

☞ They is used indefinitely, as our ancestors used man, and as the French use on; as, they say (French on dit), that is, it is said by persons not specified.

-- Webster's unabridged 1913