Disgruntled Republican enters without clothes (6)
I believe the answer is:
narked
'disgruntled' is the definition.
The answer and definition are not the same part of speech. However, adjectives and past participle verbs can sometimes mean the same thing.
'republican enters without clothes' is the wordplay.
'republican' becomes 'R' (political abbreviation).
'enters' is an insertion indicator.
'without clothes' becomes 'naked' (I've seen this in another clue).
'r' going inside 'naked' is 'NARKED'.
Can you help me to learn more?
(Other definitions for narked that I've seen before include "Angry" , "Nettled" , "Annoyed - upset - irritated" , "Annoyed (informal)" , "Cross" .)