Appeared oddly clammier (4)
I believe the answer is:
came
'appeared' is the definition.
(I've seen this in another clue)
'oddly clammier' is the wordplay.
'oddly' means one should take alternating letters (letters in the odd-numbered positions are used).
The alternating letters of 'clammier' are 'CAME'.
(Other definitions for came that I've seen before include "Appeared" , "Arrived" .)