Painfully knock (one’s toe) (4)

I believe the answer is:

stub

(Other definitions for stub that I've seen before include "Strike (a toe, say) against something hard" , "Extinguish the cigarette on a counterfoil" , "Counterfoil of cheque or butt of cigarette" , "Objections after picking up" , "Bust (anag.)" .)

I've seen this clue in The Times.

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