Nice skin of orca shimmering on sea, say, in deep water? (7)
I believe the answer is:
oceanic
'in deep water?' is the definition.
(I've seen this before)
'nice skin of orca shimmering on sea say' is the wordplay.
'skin of' means to remove the middle letters.
'shimmering' indicates anagramming the letters (letters shimmer or shake around).
'on' is a charade indicator (letters next to each other).
'say' indicates a 'sounds like' (homophone) clue.
'orca' with its centre removed is 'oa'.
'sea' sounds like 'c'.
'nice'+'oa'='niceoa'
'niceoa' anagrammed gives 'oceani'.
'oceani'+'c'='OCEANIC'
(Other definitions for oceanic that I've seen before include "In deep water" , "overwhelming" , "Relating to the open seas" , "description of rollers" , "Huge" .)