Ship in sea, noted (6)
I believe the answer is:
marked
'noted' is the definition.
('mark' can be a synonym of 'note')
'ship in sea' is the wordplay.
'ship' becomes 'ark' (I've seen this in other clues**).
'in' indicates putting letters inside.
'sea' becomes 'med' (abbreviation of Mediterranean).
'ark' placed inside 'med' is 'MARKED'.
(Other definitions for marked that I've seen before include "Read, corrected and awarded a grade" , "Pronounced" , "showing flag maybe" , "Took good notice of - . . . . . . my words?" , "Easily noticeable" .)