A jock wearing clergyman's unfashionable clothing (3,5)

I believe the answer is:

dad jeans

'unfashionable clothing' is the definition.
(sort of jeans typically worn by older men)

'a jock wearing clergyman's' is the wordplay.
'jock' becomes 'DJ' (disc jockey).
'wearing' indicates putting letters inside.
'clergyman's' becomes 'deans' (dean is a kind of clergyman).
'a'+'dj'='adj'
'adj' put inside 'deans' is 'DAD JEANS'.

I've seen this clue in The Guardian.

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