Rugby-player’s hair (4)

I believe the answer is:

lock

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'hair' is the definition.
(a lock of hair)

I don't understand the remainder of the clue.

(Other definitions for lock that I've seen before include "Clasp" , "Security device - bit of hair" , "Tress of hair" , "forward" , "Mechanism to keep closed, door say" .)

I've seen this clue in The Times.

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