To some ladies, an unpleasant creature (4)
I believe the answer is:
toad
'creature' is the definition.
(toad is a kind of creature)
'to some ladies an unpleasant' is the wordplay.
'some' means to look at the middle letters.
'ladies' becomes 'lav' (the ladies' lavatory).
'an unpleasant' becomes 'd' (I can't explain this - if you can you should believe this answer much more).
The middle of 'lav' is 'a'.
'to'+'a'+'d'='TOAD'
Can you help me to learn more?
(Other definitions for toad that I've seen before include "Stout-bodied amphibian" , "Loathsome creature" , "Ancestral hall on River Bank" , "Small amphibian" , "Contemptible person" .)