Check out ship in wild seas (6)
I believe the answer is:
assess
'check out' is the definition.
(I've seen this in another clue)
'ship in wild seas' is the wordplay.
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
'in' is an insertion indicator.
'wild' is an anagram indicator.
'seas' with letters rearranged gives 'aess'.
'ss' inserted within 'aess' is 'ASSESS'.
(Other definitions for assess that I've seen before include "(Of a tax) determine the amount to be paid" , "Appraise, estimate value" , "Fix the amount of tax" , "Gauge, evaluate" , "Remedy for all ills" .)