Meaning of “theirs” - Learner’s Dictionary

theirs

pronoun us uk /ðeəz/
His notion of fairness was different to theirs.He argued that novelists should treat their material as scientists treat theirs.We'll change our regulations when they change theirs.Although he was not a member of the group, his work resembles theirs in many ways.France lifted it ban last year, and several other countries are expected to lift theirs this year.

A2 the things that belong or relate to a group of people, animals, or things that have already been talked about:

I think she's a relation of theirs.

(Definition of “theirs” from the Cambridge Learner’s Dictionary © Cambridge University Press)