Animal on "XING" signs (4)
I believe the answer is:
deer
'animal on xing signs' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for deer that I've seen before include "Grazing animal(s)" , "The male has antlers" , "Hoofed animals" , "Like a power switch" , "Red, roe or fallow" .)