Bishop to loan mixture (5)
I believe the answer is:
blend
'mixture' is the definition.
(I know that blend is a type of mixture)
'bishop to loan' is the wordplay.
'bishop' becomes 'B' (abbreviation for bishop in chess).
'to loan' becomes 'lend' (synonyms).
'b'+'lend'='BLEND'
(Other definitions for blend that I've seen before include "Coalesce" , "Fusion" , "Amalgamate" , "Mix together" , "Mix, stir" .)