The canoe is damaged, I note, by the sea (7)
I believe the answer is:
oceanic
'the sea' is the definition.
(thesaurus)
'the canoe is damaged i note' is the wordplay.
'is damaged' indicates an anagram.
'note' becomes 'c' (musical note).
'canoe' anagrammed gives 'ocean'.
'ocean'+'i'+'c'='OCEANIC'
'by' acts as a link.
(Other definitions for oceanic that I've seen before include "Relating to large areas of sea" , "Of the open sea" , "Relating to the high seas" , "description of rollers" , "vast waves?" .)