He's committed to see AC/DC on grass (6)
I believe the answer is:
bishop
'he's committed to see' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition. I also know that 'see' relates to this answer.
'acdc on grass' is the wordplay.
'acdc' becomes 'bi' (AC/DC can informally mean bisexual).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'grass' becomes 'shop' (I've seen this before).
'bi'+'shop'='BISHOP'
Can you help me to learn more?
(Other definitions for bishop that I've seen before include "Chess piece and one of the clergy" , "whose moves cut across the rank and file" , "Senior cleric" , "one of four beginning on board" , "Chess piece; mulled wine" .)