Queen maybe describes this compiler's band (8)
I believe the answer is:
regiment
'band' is the definition.
(thesaurus)
'queen maybe describes this compiler's' is the wordplay.
'queen maybe' becomes 'regent' (a queen may rule as a regent).
'describes' is an insertion indicator (describe can mean to form the outline of).
'this compiler's' becomes 'im' ('I am' referring to the compiler of the crossword).
'regent' enclosing 'im' is 'REGIMENT'.
(Other definitions for regiment that I've seen before include "Group of battalions" , "subject to excessive control" , "The Grenadier Guards, for example" , "Part of an army" , "Army group" .)