their
/ðɛː
/possessive determiner
1Belonging to or associated with the people or things previously mentioned or easily identified: parents keen to help their children...
- It is ghastly for those who tried so hard to make the model work and who have now lost their jobs.
- They all wanted to show their grief for the loss of a girl whose life touched so many.
- People came out because they felt the power to change the world was in their own hands.
1.1Belonging to or associated with a person of unspecified sex: she heard someone blow their nose loudly...
- Anyone who wants to voice their displeasure over that lot has to do a lot of voicing.
- Why would anyone for the sake of their ego want to change the structure of what is going on?
- I am once again reminded, how wrong it is to judge a person by the colour of their skin.
2 (Their) Used in titles: a double portrait of Their Majesties...
- Their Majesties were welcomed by Her Majesty The Queen and His Royal Highness The Duke of Edinburgh at the Grand Entrance to Buckingham Palace in London.
- Their Royal Highnesses arrived shortly after 3.30pm and were introduced to several prominent Members of Parliament, local councillors and leaders.
- We were privileged and delighted to receive Their Royal Highnesses The Prince of Wales and The Duchess of Cornwall as official guests on Thursday 24 July.
Usage
1 Do not confuse their and there: their is a possessive determiner, used for example in they all tried to hide their faces and said nothing, while there is an adverb of place or position, as in I took a trip up there last week, and is used in phrases such as there is/are: we are aware there are problems. 2 On the use of their in the singular to mean ‘his or her’, see they (usage).
Origin
Middle English: from Old Norse their(r)a 'of them', genitive plural of the demonstrative sá; related to them and they.