Object to night manoeuvre (5)
I believe the answer is:
thing
'object' is the definition.
(an object is a thing or item)
'night manoeuvre' is the wordplay.
'manoeuvre' indicates anagramming the letters.
'night' anagrammed gives 'THING'.
'to' acts as a link.
(Other definitions for thing that I've seen before include "Inanimate object" , "cup of tea" , "Unspecified object" , "Individual unit" , "A creature" .)