Singer, b----- fool! (4)

I believe the answer is:

bass

'singer' is the definition.
(bass is a kind of singer)

'b-fool' is the wordplay.
'fool' becomes 'ass' (ass is a kind of fool).
'b'+'ass'='BASS'

(Other definitions for bass that I've seen before include "Fish - low voice" , "Large percussion instrument" , "Low fellow" , "Male singer and saltwater fish" , "Low-pitched; a fish" .)

I've seen this clue in The Telegraph.

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