Tip of nose surrounded by clear skin (4)
I believe the answer is:
rind
'skin' is the definition.
(synonyms)
'tip of nose surrounded by clear' is the wordplay.
'tip of' suggests taking the first letters.
'surrounded by' means one lot of letters goes inside another.
'clear' becomes 'rid' (synonyms).
The first letter of 'nose' is 'n'.
'n' inserted within 'rid' is 'RIND'.
(Other definitions for rind that I've seen before include "Outer skin of citrus fruit" , "Protective cover on cheese" , "Skin of bacon" , "Outer layer (of cheese)" , "Zest" .)