Hang on — One Direction's pants! (8)
I believe the answer is:
lingerie
'pants' is the definition.
(lingerie is a type of underwear)
'hang on one direction's' is the wordplay.
'hang on' becomes 'linger'.
'one' becomes 'i' (Roman numeral).
'direction' becomes 'e' (E is an example).
'linger'+'i'+'e'='LINGERIE'
(Other definitions for lingerie that I've seen before include "Women's underwear from France" , "Women's underclothes" , "Female underwear" , "stockings, say?" , "pants! Could be" .)