Some totally crazy stuff that clings (5)
I believe the answer is:
lycra
'stuff that clings' is the definition.
'some totally crazy' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'LYCRA' is hidden in the letters of 'totally crazy'.
(Other definitions for lycra that I've seen before include "Stretchy fabric" , "Elastomeric material" , "gear for cyclists" , "Sports clothing fabric" , "clinging fabric" .)