Ungrounded and deeply confused? (3,2,3)

I believe the answer is:

all at sea

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'confused?' is the definition.
(I've seen this in another clue)

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

(Other definitions for all at sea that I've seen before include "Situation with no sailors in port" , "Quite confused on the briny?" , "Entire crew" , "very lost" , "Is a sailor's life so" .)

I've seen this clue in The Independent.

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