Sea change (idiom)

Sea change or sea-change is an English idiomatic expression that denotes a substantial change in perspective, especially one that affects a group or society at large, on a particular issue. It is similar in usage and meaning to a paradigm shift, and may be viewed as a change to a society or community's zeitgeist, with regard to a specific issue. The phrase evolved from an older and more literal usage when the term referred to an actual "change wrought by the sea", a definition now remaining in very limited usage.