Applaud introduction of a second fastener (5)

I believe the answer is:

clasp

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'fastener' is the definition.
(I know that clasp is a type of fastener)

I don't understand how the remainder of the clue works.

(Other definitions for clasp that I've seen before include "Hug" , "Grip firmly" , "Handshake or fastening device" , "Grasp tightly" , "bosom" .)

I've seen this clue in the Sydney Morning Herald.

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