Una upset with sea sickness (6)

I believe the answer is:

nausea

'sickness' is the definition.
(I know that sickness can be written as nausea)

'una upset with sea' is the wordplay.
'upset with' indicates anagramming the letters.
'una' mixed up with 'sea' can make 'NAUSEA'.

(Other definitions for nausea that I've seen before include "Feeling of imminent sickness, may be caused by sea" , "Feeling of imminent sickness or upset stomach" , "Condition of feeling imminent sickness" , "Squeamishness" , "Unpleasant feeling" .)

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

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