Mammal of giraffe family (5)
I believe the answer is:
okapi
'mammal of giraffe family' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for okapi that I've seen before include "Ruminant mammal of Africa" , "African animal like giraffe with shorter neck and striped body" , "Animal of the giraffe family (much loved by crossword setters)" , "Animal of central Africa" , "Ruminant related to the giraffe" .)