Ru″in (?), n. [OE. ruine, F. ruine, fr. L. ruina, fr. ruere, rutum, to fall with violence, to rush or tumble down.] 1. The act of falling or tumbling down; fall. “His ruin startled the other steeds.” Chapman.
2. Such a change of anything as destroys it, or entirely defeats its object, or unfits it for use; destruction; overthrow; as, the ruin of a ship or an army; the ruin of a constitution or a government; the ruin of health or hopes. “Ruin seize thee, ruthless king!” Gray.
3. That which is fallen down and become worthless from injury or decay; as, his mind is a ruin; especially, in the plural, the remains of a destroyed, dilapidated, or desolate house, fortress, city, or the like.
The Veian and the Gabian towers shall fall,
And one promiscuous ruin cover all;
Nor, after length of years, a stone betray
The place where once the very ruins lay. Addison.
The labor of a day will not build up a virtuous habit on the ruins of an old and vicious character. Buckminster.
4. The state of being dcayed, or of having become ruined or worthless; as, to be in ruins; to go to ruin.
5. That which promotes injury, decay, or destruction.
The errors of young men are the ruin of business. Bacon.
Syn. — Destruction; downfall; perdition; fall; overthrow; subversion; defeat; bane; pest; mischief.