Surplus to requirements (5)
There are a few possibilities for this:
redundant
'surplus to requirements' is the definition.
(extra can mean spare or unneeded)
This is all the clue.
(Other definitions for extra that I've seen before include "Possibly overthrow" , "late edition" , "Cricket run; unusually" , "Minor person screened" , "spotted at rear of the platoon?" .)
'surplus to requirements' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for spare that I've seen before include "Excess to requirements" , "Thin; left over" , "Thin; surplus" , "slit at top of trousers in Scotland" , "A feature of trousers" .)
'surplus to requirements' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for redundant that I've seen before include "Surplus to requirements" , "laid off" , "without useful purpose" , "out of a job" , "on the scrap heap?" .)