ru·in / ˈroōin/ • n. the physical destruction or disintegration of something or the state of disintegrating or being destroyed: a large white house falling into gentle ruin. ∎  the remains of a building, typically an old one, that has suffered much damage or disintegration: the ruins of the castle the church is a ruin now. ∎  the disastrous disintegration of someone's life: the ruin and heartbreak wrought by alcohol, divorce, and violence. ∎  the cause of such disintegration: they don't know how to say no, and that's been their ruin. ∎  the complete loss of one's money and other assets: the financial cost could mean ruin.• v. 1. [tr.] reduce (a building or place) to a state of decay, collapse, or disintegration: [as adj.] (ruined) a ruined castle. ∎  cause great and usually irreparable damage or harm to; have a disastrous effect on: a noisy freeway has ruined village life. ∎  reduce to a state of poverty: they were ruined by the highest interest rates this century.2. [intr.] poetic/lit. fall headlong or with a crash: carriages go ruining over the brink from time to time.PHRASES: in ruins in a state of complete disorder or disintegration: the economy was in ruins.ORIGIN: Middle English (in the sense ‘collapse of a building’): from Old French ruine, from Latin ruina, from ruere ‘to fall.’

ruin. Carefully contrived specially constructed ‘ruins’ (sometimes called folly) or real ruins (e.g. of a castle or abbey) were often incorporated within C18 English Picturesque landscapes, a fashion that spread to Europe. Some architects (e.g Chambers and Soane) established their architectural works as worthy of the best Classical Antique models by arranging for them to be depicted as imaginary ruins, inspired by the Grand Tour and the influential engravings of Piranesi.

Bibliography

D. Coffin (1994);
D. Jacques (1983);
M&T (1991);
Jane Turner (1996)

ruin (state consequent upon) giving way and falling down XIV (concr. XV); downfall, utter loss XIV. — (O)F. ruine — L. ruīna, f. ruere fall.
So vb. XVI. — (O)F. ruiner or medL. ruīnāre. †ruinate, ruination XVI. ruinous XIV. — (O)F. or L. ruīnōsus.