By the sound of it gather a crowd (5)

I believe the answer is:

horde

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'crowd' is the definition.
(I know that horde is a type of crowd)

I cannot understand how the rest of the clue works.

(Other definitions for horde that I've seen before include "A moving crowd" , "Nomadic army" , "Large group of people" , "Host" , "Many people" .)

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

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