Irregular forces decoration (6)
I believe the answer is:
fresco
'decoration' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe there's a link between them I don't understand?
'irregular forces' is the wordplay.
'irregular' indicates anagramming the letters.
'forces' is an anagram of 'FRESCO'.
Can you help me to learn more?
(Other definitions for fresco that I've seen before include "Method of painting on walls" , "Forces (anag) - wall painting" , "Wall-painting" , "Painting done in wet plaster" , "Mode of wall painting" .)