Leave quietly to take undergarment off? (4,4)

I believe the answer is:

slip away

'leave quietly' is the definition.
(synonyms)

'undergarment off?' is the wordplay.
'undergarment' becomes 'slip' (slip is a kind of undergarment).
'off?' becomes 'away' (synonyms).
'slip'+'away'='SLIP AWAY'

'to take' acts as a link.

I've seen this clue in The Irish Times.

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