Missing resin-like material for monarch (7)
I believe the answer is:
lacking
'missing resin' is the definition.
'lacking' can be an answer for 'missing' (lacking is a kind of missing). I am not sure about the 'resin' bit.
'like material for monarch' is the wordplay.
'like material' becomes 'lac' (lac is a kind of material. I am not sure about the 'like' bit.).
'for' is a charade indicator (letters next to each other).
'monarch' becomes 'king' (king is a kind of monarch).
'lac'+'king'='LACKING'
Can you help me to learn more?
(Other definitions for lacking that I've seen before include "Absent, deficient" , "'Deficient, wanting (7)'" , "Missing" , "Deficient or inadequate" , "Short" .)