Small piece preceding Taverner's first choral work (5)
I believe the answer is:
motet
'choral work' is the definition.
(I've seen this before)
'small piece preceding taverner's first' is the wordplay.
'small piece' becomes 'mote' (I am not sure about this - if you are sure you should believe this answer much more).
'preceding' is a charade indicator (letters next to each other).
'taverner's first' becomes 't' (mst letter of 'taverner').
'mote'+'t'='MOTET'
Can you help me to learn more?
(Other definitions for motet that I've seen before include "Certain one is morally superior" , "Short sacred choral piece" , "Piece for choir" , "Short sacred vocal work" , "Piece of sacred music" .)