Bunyan's blue ox (4)
I believe the answer is:
babe
'bunyan's blue ox' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for babe that I've seen before include "Very young child (often found in arms)" , "Ruth, for example" , "Term of endearment" , "Darling" , "A literary infant or a modern good-looking girl" .)