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Synonyms

fortuitous

American  
[fawr-too-i-tuhs, -tyoo-] / fɔrˈtu ɪ təs, -ˈtyu- /

adjective

  1. happening or produced by chance; accidental.

    a fortuitous encounter.

    Synonyms:
    incidental
  2. lucky; fortunate.

    a series of fortuitous events that advanced her career.


fortuitous British  
/ fɔːˈtjuːɪtəs /

adjective

  1. happening by chance, esp by a lucky chance; unplanned; accidental

"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

Commonly Confused

Fortuitous has developed in sense from “happening by chance” to “happening by lucky chance” to simply “lucky, fortunate.” This development was probably influenced by the similarity of fortuitous to fortunate and perhaps to felicitous : A fortuitous late-night snowfall made for a day of great skiing. Many object to the use of fortuitous to mean simply “fortunate” and insist that it should be limited to its original sense of “accidental.” In modern standard use, however, fortuitous almost always carries the senses both of accident or chance and luck or fortune. It is infrequently used in its sense of “accidental” without the suggestion of good luck, and even less frequently in the sense “lucky” without at least a suggestion of accident or chance: A fortuitous encounter with a former schoolmate led to a new and successful career for the artist.

Related Words

See accidental.

Other Word Forms

Etymology

Origin of fortuitous

First recorded in 1645–55; from Latin fortuitus, fortuītus, equivalent to fortu- (u-stem base, otherwise unattested, akin to fors, genitive fortis “chance, luck”) + -itus, -ītus adjective suffix (for formation cf. gratuitous); see -ous

Explanation

Fortuitous means by chance, like a lucky accident. If you and your best friend's families happen to go on vacation to the same place at the same time, that’s a fortuitous coincidence! Something fortuitous is random like an accident, but there’s no downside. A rock falling on your head is an accident, dollar bills falling on your head is fortuitous. The meaning of fortuitous is changing from "happening by chance" to "lucky chance" because people get it mixed up with fortunate. But watch out: If you say fortuitous to mean just plain lucky without the element of chance — that's a usage error.

Keep Reading on Vocabulary.com

Vocabulary lists containing fortuitous

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.

The purchases have proven to be a fortuitous windfall for refiners who largely steered clear of both suppliers previously to avoid US ire.

From Barron's • Apr. 26, 2026

Apple’s pocket music player largely owed its existence to one fortuitous meeting Apple executives had with the maker of a tiny hard drive that didn’t seem to have any practical application.

From The Wall Street Journal • Mar. 6, 2026

This purchase was especially fortuitous as the facility was in an area already zoned to permit a medical clinic.

From Slate • Jan. 13, 2026

To her, it’s fortuitous timing so many milestones have occurred in the past 12 months.

From Los Angeles Times • Dec. 17, 2025

Maybe it had seemed to Kabuo Miyamoto, alone on the sea shortly afterward, a fortuitous thing to have come across Carl Heine in circumstances such as these.

From "Snow Falling on Cedars: A Novel" by David Guterson