Catching criminal before mark promises to pay (10)

I believe the answer is:

contagious

'catching' is the definition.
('contagious' can be a synonym of 'catching')

'criminal before mark promises to pay' is the wordplay.
'criminal' becomes 'con' (abbreviation for 'convict').
'before' says to put letters next to each other.
'mark' becomes 'tag' (tag is a kind of mark).
'promises to pay' becomes 'ious' (more than one iou).
'con'+'tag'+'ious'='CONTAGIOUS'

(Another definition for contagious that I've seen is " Catching".)

I've seen this clue in The Telegraph.

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