I. ros ‧ ter 1 /ˈrɒstə $ ˈrɑːstər/ BrE AmE noun [countable]
[ Date: 1700-1800 ; Language: Dutch ; Origin: rooster 'frame for cooking things on, list' , from roosten 'to roast' ]
1 . a list of the names of people on a sports team, in an organization etc
on a roster
The club has outstanding players on the roster.
roster of
The campaign has a roster of 500 volunteers.
2 . a list that shows when each person in a group must do a particular job SYN rota British English :
duty roster
II. roster 2 BrE AmE verb [transitive]
to put someone’s name on a roster