Sea change definitions

Sea change

1) American detective novel 2) American thriller novel 3) British adventure novel 4) English-language idiom
Found on https://www.crosswordclues.com/clue/sea-change

[transformation] Sea-change or seachange, according to the Oxford English Dictionary, means `a change wrought by the sea.` The term originally appears in William Shakespeare`s The Tempest in a song sung by a supernatural spirit, Ariel, to Ferdinand, a prince of Naples, after Ferdinand`s father`s apparent death by drowning: `Full fathom five...
Found on http://en.wikipedia.org/wiki/Sea_change_(transformation)