Vessel often crossing the bar (8)

I believe the answer is:

schooner

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'vessel' is the definition.
(type of ship)

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

(Other definitions for schooner that I've seen before include "A measure or glass for sherry" , "Measure for sherry or kind of sailing ship" , "9 [CONTAINER" , "boat" , "In the main it is" .)

I've seen this clue in The Globe and Mail.

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