Remaining port getting finished (8)
I believe the answer is:
leftover
'remaining' is the definition.
(I know that remaining can be written as leftover)
'port getting finished' is the wordplay.
'port' becomes 'left' (port is the left side on a boat).
'getting' says to put letters next to each other.
'finished' becomes 'over' (over can mean finished or ended).
'left'+'over'='LEFTOVER'
(Other definitions for leftover that I've seen before include "Finally unused" , "something you'd keep on the plate!" , "What remains" , "Remaining" , "Remnant" .)