Gushing tap at basin for adult inducted in water ceremony? (10)

I believe the answer is:

anabaptist

'adult inducted in water ceremony?' is the definition.
(anabaptists perform adult baptisms)

'gushing tap at basin' is the wordplay.
'gushing' is an anagram indicator.
'tap'+'at'+'basin'='tapatbasin'
'tapatbasin' anagrammed gives 'ANABAPTIST'.

'for' acts as a link.

(Another definition for anabaptist that I've seen is " Protestant sect member".)

I've seen this clue in The Guardian.

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