Evidently the dean would accept his company (6)
I believe the answer is:
deacon
'evidently the dean would accept his company' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'would accept his company' is the wordplay.
I cannot quite see how this works, but
'would' could be 'd' (as in 'we'd' - 'we would') and 'd' is found in the answer.
'company' could be 'co' (abbreviation) and 'co' is found in the answer.
The remaining letters 'ean' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for deacon that I've seen before include "Churchman" , "Christian rank below a priest" , "Church post" , "Rank of clergy" , "An ordained minister" .)