Little animal's not entirely clever (5)
I believe the answer is:
shrew
'little animal's' is the definition.
'shrew' can be an answer for 'animal's' (shrew is a kind of animal). I am unsure of the 'little' bit.
'not entirely clever' is the wordplay.
'not entirely' means to remove the last letter (not all of the word).
'clever' becomes 'shrewd' (I've seen this in another clue).
'shrewd' with its final letter taken away is 'SHREW'.
Can you help me to learn more?
(Other definitions for shrew that I've seen before include "Vixen" , "difficult woman" , "Mouse-like creature" , "Scold, termagant" , "Petruchio tamed one" .)