ˈfill-in BrE AmE noun [singular] British English informal
someone who does someone else’s job because that person is not there SYN stand-in :
I’m here as a fill-in while Robert’s away.
ˈfill-in BrE AmE noun [singular] British English informal
someone who does someone else’s job because that person is not there SYN stand-in :
I’m here as a fill-in while Robert’s away.
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012