Aims to finish before start of supper (4)
I believe the answer is:
ends
'aims' is the definition.
(I've seen this before)
'finish before start of supper' is the wordplay.
'finish' becomes 'end' ('end' can be a synonym of 'finish'**).
'before' says to put letters next to each other.
'start of' says to take the initial letters.
The initial letter of 'supper' is 's'.
'end'+'s'='ENDS'
'to' acts as a link.
(Other definitions for ends that I've seen before include "limits" , "See 8" , "Terminates in dens" , "Send to conclusions" , "Extremities" .)