Threw small organ (5)
I believe the answer is:
slung
'threw' is the definition.
(I've seen this in another clue)
'small organ' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'organ' becomes 'lung' (lung is a kind of organ).
's'+'lung'='SLUNG'
(Other definitions for slung that I've seen before include "Hurled" , "Threw out" , "Thrown; suspended loosely" .)