Whirlwind decapitated cuddly toy (4)
I believe the answer is:
eddy
'whirlwind' is the definition.
(I've seen this before)
'decapitated cuddly toy' is the wordplay.
'decapitated' means to remove the first letter.
'cuddly toy' becomes 'teddy' (I've seen this before).
'teddy' with its initial letter taken off is 'EDDY'.
(Other definitions for eddy that I've seen before include "Fellow" , "Vortex" , "Little swirl in water" , "Spin" , "Man" .)