Hardline communist, not a wet (5)
I believe the answer is:
moist
'a wet' is the definition.
(I've seen this before)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for moist that I've seen before include "Slightly wet, damp" , "Affected by tears, perhaps" , "sloppy" , "Damp or clammy" , "Dampish" .)