Bled once cold increased (6)

I believe the answer is:

cupped

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'bled' is the definition.
The answer and definition can be both related to bodily activities as well as being past participle verbs.
Maybe there's an association between them I don't understand?

'cold increased' is the wordplay.
'cold' becomes 'C' (eg on taps).
'increased' becomes 'upped' (upping is a kind of increasing).
'c'+'upped'='CUPPED'

'once' is the link.

Can you help me to learn more?

I've seen this clue in The Times.

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