Word Study
their
CIDE DICTIONARY
their, pron. & a. [OE. thair, fr. Icel. þeirra, þeira, of them, but properly gen. pl. of the definite article; akin to AS. &edh;āra, &edh;\'d6ra, gen. pl. of the definite article, or fr. AS. &edh;\'d6ra, influenced by the Scandinavian use. See That.].
The possessive case of the personal pronoun they; as, their houses; their country. [1913 Webster]
" The possessive takes the form theirs (theirs is best cultivated." [1913 Webster]
"Nothing but the name of zeal appears
'Twixt our best actions and the worst of theirs." [1913 Webster]
'Twixt our best actions and the worst of theirs." [1913 Webster]
OXFORD DICTIONARY
their, poss.pron. (attrib.)
1 of or belonging to them or themselves (their house; their own business).
2 (Their) (in titles) that they are (Their Majesties).
3 disp. as a third person sing. indefinite meaning 'his or her' (has anyone lost their purse?).
1 of or belonging to them or themselves (their house; their own business).
2 (Their) (in titles) that they are (Their Majesties).
3 disp. as a third person sing. indefinite meaning 'his or her' (has anyone lost their purse?).
Etymology
ME f. ON their(r)a of them, genit. pl. of s{aacute} THE, THAT
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