Crossword Genius

Vessels for instance at sea withdrawing loudly (10)

Ross

I believe the answer is:

containers

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

'vessels' is the definition.
(vessel can mean a container)

'instance at sea withdrawing loudly' is the wordplay.
I cannot quite understand how this works, but
'at' could be 'on' (location) and 'on' is found in the answer.
This may be the basis of clue (or it may be nonsense).

'for' is the link.

Can you help me to learn more?

I've seen this clue in The Telegraph.
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