Their
Their , pronoun and adjective
[Old English thair, from Icelandic þeirra, þeira, of them, but properly gen. plural of the definite article; akin to Anglo-Saxon eāra, eara, gen. plural of the definite article, or from Anglo-Saxon eara, influenced by the Scandinavian use. See That.]
The possessive case of the personal pronoun they; as, their houses; their country.
Nothing but the name of zeal appears
'Twixt our best actions and the worst of theirs.
The possessive takes the form theirs ({not transcribed}) when the noun to which it refers is not expressed, but implied or understood; as, our land is richest, but theirs is best cultivated.