Definitions

1. pronoun

belonging to them; used especially to emphasize that something belongs to or is associated with the people referred to by ‘they’, ‘them’, or ‘themself’

“Their car is parked on the street.”

2. adjective

relating to or characteristic of them

“Their ideas were interesting.”

3. noun

a group of people together, especially with shared qualities or interests

“Their team is doing well in the competition.”