Inflatable sheep found in Spar (3,4)
I believe the answer is:
mae west
'inflatable' is the definition.
(I've seen this before)
'sheep found in spar' is the wordplay.
'sheep' becomes 'ewe' (a ewe is a female sheep).
'found in' indicates putting letters inside.
'spar' becomes 'mast' (mast is a kind of spar).
'ewe' placed within 'mast' is 'MAE WEST'.
(Other definitions for mae west that I've seen before include "Life jacket; film star" , "20th century film star (Diamond Lil)" , "Ex-player" , "embraced many men in the main" , "Old safety clothing" .)