their
UK /ðɛə/ · US /ðɛɚ/ determiner
Also a form of they
Forms deir thair theire theyr theyre thir
- determiner Belonging to, from, of, or relating to, them (plural). “they will meet tomorrow at their convenience”
- determiner Belonging to someone (one person, singular), or occasionally to something.
Etymology
From Old Norse þeira, þeirra. Replaced native Old English heora.
Webster’s 1913
Etymology [OE. thair, fr. Icel. Þeirra, Þeira, of them, but properly gen. pl. of the definite article; akin to AS. th\'bera, th\'d6ra, gen. pl. of the definite article, or fr. AS. th\'d6ra, influenced by the Scandinavian use. See That.]
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “their”, CC BY-SA 4.0. Details