Precise account supported by clergyman (8)
I believe the answer is:
accurate
'precise' is the definition.
(similar in meaning)
'account supported by clergyman' is the wordplay.
'account' becomes 'ac' (abbreviation for account).
'supported by' is a charade indicator (letters next to each other) (in a down clue, some letters hold up others).
'clergyman' becomes 'curate' (curate is a kind of clergyman).
'ac'+'curate'='ACCURATE'
(Other definitions for accurate that I've seen before include "not deviating from the truth?" , "Spot-on" , "True!" , "Absolutely correct" , "Totally correct" .)