Get a move on and stamp out garrulity? (4,2,3,3)

I believe the answer is:

step on the gas

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'get a move on' is the definition.
(I've seen this in another clue)

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

(Other definitions for step on the gas that I've seen before include "Drive faster" , "Hurry" , "Speed up" .)

I've seen this clue in The Globe and Mail.

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