Drug needed on Arctic manoeuvres (8)
I believe the answer is:
narcotic
'drug' is the definition.
(I've seen this before)
'on arctic manoeuvres' is the wordplay.
'manoeuvres' is an anagram indicator.
'on'+'arctic'='onarctic'
'onarctic' is an anagram of 'NARCOTIC'.
'needed' acts as a link.
(Other definitions for narcotic that I've seen before include "this will induce numbness" , "Drug producing numbness and stupor" , "A sleep-inducing drug" , "A drug causing sleep or drowsiness" , "Drug that produces numbness or stupor" .)