Definition of ruinatious in English:

ruinatious

adjective

Southern, West, United States Regional
rare
  • That brings or tends to bring ruin; ruinous, disastrous.

Origin

Mid 19th century; earliest use found in Sylvester Judd (1813–1853), novelist. From ruinate + -ious.

Pronunciation

ruinatious

/ˌruːɪˈneɪʃəs/