Merchant having less money (6)

I believe the answer is:

broker

I'm a little stuck... Click here to teach me more about this clue!

'merchant' is the definition.
(thesaurus)

I cannot understand how the rest of the clue works.

(Other definitions for broker that I've seen before include "See 7" , "Negotiate with" , "One acts as an agent for others in buying and selling" , "Middleman, dealer" , "Agent paid by commission" .)

I've seen this clue in The Mirror.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.