A lot of money for a bun! (3)

I believe the answer is:

wad

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

'a lot of money' is the definition.
(wad of cash)

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

(Other definitions for wad that I've seen before include "A thick bundle, maybe of money" , "Bundle of soft material or of banknotes" , "Compact mass" , "Small bundle" , "Bankroll; sandwich (slang)" .)

I've seen this clue in the Evening Standard.

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.