You could quote a weight for this vessel (3)

I believe the answer is:

tun

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

'for this vessel' is the definition.
(tun is a kind of vessel)

I can't explain the remainder of the clue.

(Other definitions for tun that I've seen before include "One can hold wine" , "Container of beer" , "'Large cask, for beer perhaps (3)'" , "beer barrel" , "Large cask (holding 252 gallons)" .)

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.