Crossword Genius

What winds one up in firm's do? (5)

Ross

I believe the answer is:

feast

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

'do?' is the definition.
(thesaurus)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for feast that I've seen before include "Banquet or religious festival" , "Celebratory meal" , "Big meal" , "Lavish meal" , "Huge nosh-up" .)

I've seen this clue in The Telegraph.
Want a hint initially instead of a full solution? Install my app