Menial boxers, say, joining main group (8)
I believe the answer is:
dogsbody
'menial' is the definition.
(synonyms)
'boxers say joining main group' is the wordplay.
'boxers say' becomes 'dogs' (boxer is a kind of dog).
'joining' is a charade indicator (letters next to each other).
'main group' becomes 'body' (body can mean an organisation or group. I am not sure about the 'main' bit.).
'dogs'+'body'='DOGSBODY'
Can you help me to learn more?
(Other definitions for dogsbody that I've seen before include "One who carries out menial tasks for another" , "One given menial tasks" , "The one who does all the menial, boring work" , "Menial servant" , "General factotum" .)