Extra pears are ordered (5)
I believe the answer is:
spare
'extra' is the definition.
('spare' can be a synonym of 'extra')
'pears are ordered' is the wordplay.
'are ordered' indicates an anagram.
'pears' anagrammed gives 'SPARE'.
(Other definitions for spare that I've seen before include "This tyre around the middle is fat" , "A feature of trousers" , "show mercy" , "Pardon; unneeded" , "Not required" .)