Sheep-like (5)
I believe the answer is:
ovine
'sheep-like' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for ovine that I've seen before include "1/6 = 2/3 of 28 [SHEEPISH" , "like a mug" , "Resembling a sheep" , "Like the Cheviots" , "Like a sheep" .)