UK:*UK and possibly other pronunciationsUK and possibly other pronunciations/ˈruːɪnəs/US:USA pronunciation: IPA and respellingUSA pronuncation: IPA/ˈruənəs/ ,USA pronunciation: respelling(ro̅o̅ə nəs)

WordReference Random House Learner's Dictionary of American English © 2020
ru•in•ous /ˈruənəs/USA pronunciation  adj. 
  1. bringing or likely to cause ruin:a ruinous war.
ru•in•ous•ly, adv.: Moving to another town would have been ruinously expensive.

WordReference Random House Unabridged Dictionary of American English © 2020
ru•in•ous  (ro̅o̅ə nəs),USA pronunciation adj. 
  1. bringing or tending to bring ruin;
    disastrous:a ruinous war.
  2. fallen into ruin;
    dilapidated:a ruinous house.
  3. consisting of ruins:a ruinous city from antiquity.
ruin•ous•ly, adv. 
ruin•ous•ness, n. 
  • Latin ruīnōsus, equivalent. to ruīn(a) ruin + -ōsus -ous
  • Middle English ruynouse 1350–1400
    • 1.See corresponding entry in Unabridged calamitous, ravaging, devastating, catastrophic.

Collins Concise English Dictionary © HarperCollins Publishers::
ruinous /ˈruːɪnəs/ adj
  1. causing, tending to cause, or characterized by ruin or destruction

ˈruinously adv ˈruinousness n
'ruinous' also found in these entries:

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