Not required (8)
'not required' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for optional that I've seen before include "Too plain (anag.)" , "Such as one can take or leave" , "'Elective, not obligatory (8)'" , "Voluntary - not required" , "Not mandatory" .)
(Other definitions for needless that I've seen before include "Gratuitous" , "Lessened, being without good cause" , "Excessive" , "luxury" , "without provocation?" .)
'not required' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for unwanted that I've seen before include "Outcast" , "Superfluous" , "Left over" , "Not required" , "redundant" .)
(Other definitions for unneeded that I've seen before include "Surplus to requirements" , "Not neccessary" , "Not necessary" .)