Lift is warm outside (5)
I believe the answer is:
hoist
'lift' is the definition.
(hoist can mean to lift something up)
'is warm outside' is the wordplay.
'warm' becomes 'hot' (associated in meaning).
'outside' indicates putting letters inside (some letters go outside others).
'is' placed inside 'hot' is 'HOIST'.
(Other definitions for hoist that I've seen before include "Lift using pulley and ropes" , "Raise on pulleys" , "Lift, raise" , "Lift with rope and pulley" , "Elevate" .)