Singers missing start — God! (5)
I believe the answer is:
horus
'god' is the definition.
(Egyptian god)
'singers missing start' is the wordplay.
'singers' becomes 'chorus' (chorus can mean a group of singers).
'missing start' means to remove the first letter.
'chorus' with its first letter removed is 'HORUS'.
(Other definitions for horus that I've seen before include "Deity" , "Falcon-headed old Egyptian god" , "Falcon-headed god of ancient Egypt" , "Egyptian god of the sun" , "Egyptian hawk-headed god" .)