Short tail (4)
I believe the answer is:
scut
'short tail' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for scut that I've seen before include "(Hare's) short upright tail" , "Short tail, such as rabbit's" , "Reindeer's tail" , "Reindeer tail" , "Short tail of hare" .)