line-up [countable usually singular]
the players in a sports team who play in a particular game:
This was his first match in the starting line-up (=the players who begin the game).
a group of people, especially performers, who have agreed to be involved in an event:
The line-up included top bands Prodigy and Radiohead.
a number of events or programmes arranged to follow each other:
a wonderful line-up of programmes for Christmas and the New Year
4 especially American EnglishSC
a row of people who stand in front of a witness to a crime, who is then asked if he or she recognizes any of them as the criminal [= identification parade British English]