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Synonyms

ruinous

American  
[roo-uh-nuhs] / ˈru ə nəs /

adjective

  1. bringing or tending to bring ruin; destructive; disastrous.

    a ruinous war.

    Synonyms:
    catastrophic, devastating, calamitous
  2. fallen into ruin; dilapidated.

    a ruinous house.

  3. consisting of ruins.

    a ruinous city from antiquity.


ruinous British  
/ ˈruːɪnəs /

adjective

  1. causing, tending to cause, or characterized by ruin or destruction

    a ruinous course of action

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • nonruinous adjective
  • nonruinously adverb
  • nonruinousness noun
  • ruinously adverb
  • ruinousness noun
  • unruinous adjective
  • unruinously adverb
  • unruinousness noun

Etymology

Origin of ruinous

1350–1400; Middle English ruynouse < Latin ruīnōsus, equivalent to ruīn ( a ) ruin + -ōsus -ous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“It’s been years that we’ve been warning management about the ruinous state of equipment and lack of adequate staffing.”

From The Wall Street Journal

“It seems to me this is a 60-40 choice,” he said, adding neither outcome would be ruinous: “I don’t think it’s a huge policy error on either side.”

From The Wall Street Journal

I won’t spoil how, but it’s emotionally ruinous for the people involved, even if Mr. Laxe stages it with a bit of cheapening suspense.

From The Wall Street Journal

John Kennedy’s greatest fear was that he and Nikita Khrushchev were making the same mistakes as past leaders, bumbling down the same ruinous road.

From Literature

The Lakota leader Sitting Bull defeated George Custer’s cavalry, but a sustained conflict with American forces proved ruinous.

From The Wall Street Journal