# theirs vs theory

> English confusable word pair

## The two words

### theirs
*pronoun · IPA /ðɛəz/ · frequency rank #7,623*
That or those belonging to them; the possessive case of they, used without a following noun.

### theory
*noun · IPA /ˈθɪə.ɹi/ · frequency rank #1,412*
A description of an event or system that is considered to be accurate.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/vs/theirs-vs-theory