Mammal takes short rope over with grace (8)
I believe the answer is:
porpoise
'mammal' is the definition.
(I've seen this before)
'short rope over with grace' is the wordplay.
'short' means to remove the last letter.
'over' shows that the letters should be reversed in order.
'with' says to put letters next to each other.
'grace' becomes 'poise' (I've seen this in another clue).
'rope' with its final letter removed is 'rop'.
'rop' back-to-front is 'por'.
'por'+'poise'='PORPOISE'
'takes' is the link.
(Other definitions for porpoise that I've seen before include "Small aquatic mammal with blunt snout" , "Swimmer" , "Cetacean" , "Animal" , "Marine mammal" .)