1630s, "laying waste, ravaging," present-participle adjective from devastate. Trivial or hyperbolic use is by 1889.
The noun is attested from 1520s, originally in the grammatical sense, "a word in the superlative;" hence "exaggerated language" (1590s).
Middle English sein, "visible, able to be seen with the eyes; plain, clear, manifest," from Old English gesegen, gesewen, past participle of seon (see see (v.)). From c. 1200 as "perceived, discovered." From c. 1300 as "experienced, undergone." To have seen everything as a hyperbolic expression of astonishment is from 1941 (the phrase itself is older, in "Gatsby," etc.).
He that has seen one thing hath seen all things ; for he has got the general idea of something. [Locke, 1706]
The saw or vulgar maxim about children being best seen and not heard (by 1816) was previously of maids specifically (mid-15c.).
Well, at length my wish was in part gratified—lady Cowley was announced. It has been said that women, like children, should be "seen and not heard." I am no advocate for dumb dolls, yet I object to catching the voice through long passages ere one sees the party, and in the present instance ... (etc.) ["The Spinster's Journal," vol. 1, by 'A Modern Antique,' London: 1816]