■ possessive determiner
1》 belonging to or associated with the people or things previously mentioned or easily identified.
2》 belonging to or associated with a person of unspecified sex (used in place of either ‘his’ or ‘his or her’).
3》 ( Their ) used in titles.
Origin
ME: from ON ~(r)a 'of them', genitive plural of the demonstrative sá ; related to them and they .
Usage
Do not confuse ~ and there . Their means ‘belonging to them’ ( I went to ~ house ) while there means ‘in, at, or to that place’ ( it took an hour to get there ).
On the use of ~ in the singular to mean ‘his or her’, see usage at they .