noun

1. Archaic a falling down, as of a building, wall, etc.
2. the remains of a fallen building, city, etc., or of something devastated, decayed, etc.
3. 1. a destroyed or dilapidated building, town, etc.
   2. a person regarded as being physically, mentally, or morally a wreck of what he or she was
4. the state of being destroyed, decayed, dilapidated, etc.
5. downfall, destruction, devastation, etc.; specif.,
   1. complete loss of means, solvency, position, etc.
   2. moral downfall
   3. loss of chastity in a woman
6. any cause of a person's downfall, destruction, etc. gambling was his ruin

Etymology: ME ruine < OFr < L ruina < ruere, to fall, hurl to the ground < IE *ereu- < base *er-, to set in motion, erect > run, rise

transitive verb

intransitive verb