Past ace has to give way (3)
I believe the answer is:
ago
'past' is the definition.
(I've seen this before)
'ace has to give way' is the wordplay.
'ace' becomes 'a'.
'has' is a charade indicator (letters next to each other).
'to give way' becomes 'go' ('go' can be a synonym of 'give way').
'a'+'go'='AGO'
(Other definitions for ago that I've seen before include "Back (in time)" , "In past times" , "Earlier, gone by" , "(Years) before the present time" , "Gone, past, since" .)