ru·​in·​ous ˈrü-ə-nəs How to pronounce ruinous (audio)
: causing or tending to cause ruin
ruinously adverb
ruinousness noun

Example Sentences

The house has fallen into a ruinous state. a ruinous miscalculation of the financial markets left them bankrupt
Recent Examples on the Web Middle-earth is attempting to move on from a ruinous war with Morgoth, a godlike being from whom all evil stems, as well as his chief lieutenant: none other than Sauron himself. Michael Nordine, Variety, 1 Sep. 2022 The United States and apartheid-era South Africa supported the MPLA’s chief military rival, known by the acronym UNITA, fueling a ruinous superpower proxy war for control of Angola. Bob Drogin, Washington Post, 8 July 2022 Recognizing Somerset as a legal person would not just liberate a single individual but set a precedent that could be financially ruinous for slaveholders. Lawrence Wright, The New Yorker, 28 Feb. 2022 Violating that omertà can bring ruinous consequences for a young clerk’s professional prospects. Matt Ford, The New Republic, 6 Oct. 2022 The only way to deter any possible use of nuclear weapons is to make Mr. Putin believe that the consequences of such use will be ruinous for Russia as a state and for him as its ruler, and that the West won’t flinch when the time for action comes. Walter Russell Mead, WSJ, 6 Oct. 2022 And fickle analysis has left confidence in the polls shaky at best and ruinous in reality. Philip Elliott, Time, 21 Oct. 2022 Surfaces of the shoes matter, as rougher fabric surfaces would capture more DNA and metal in buckles could cause a ruinous chemical reaction in some circumstances, such as environmental exposure. Meredith Cohn, Washington Post, 20 Oct. 2022 These were especially destabilizing in Germany, where the armistice had imposed ruinous economic reparations. Timothy Noah, The New Republic, 12 Sep. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ruinous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of ruinous was in the 14th century

Dictionary Entries Near ruinous

Cite this Entry

“Ruinous.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2022.

Kids Definition



ru·​in·​ous ˈrü-ə-nəs How to pronounce ruinous (audio)
: causing or tending to cause ruin : destructive
ruinously adverb

More from Merriam-Webster on ruinous

Last Updated: - Updated example sentences
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