INFORMAL Synonyms: 85 Similar and Opposite Words

informal

adjective

(ˌ)in-ˈfȯr-məl

Definition of informal

as in unconventional

not rigidly following established form, custom, or rules an informal meeting allowed everyone to get acquainted

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in casual

not designed to be worn only on special occasions chose an informal flowery dress

Synonyms & Similar Words

Antonyms & Near Antonyms

as in colloquial

used in or suitable for speech and not formal writing the use of informal language in a scholarly article is really inappropriate

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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Recent Examples of informal Organizers arranged nearly two dozen panel sessions throughout the day, letting participants choose among six smaller conversations at several points during the day, while leaving room for informal chats in the gardens. — Elsa Keslassy, Variety, 11 Sep. 2026 The request was made after informal discussions between the Justice Department and British law enforcement did not produce the unredacted information, the Times reported. — Arkansas Online, 10 Sep. 2026 The episode became a turning point, unraveling diplomacy that had largely preserved the informal truce and halted Houthi attacks on Saudi territory. — Nic Robertson, CNN Money, 10 Sep. 2026 But the curbs nevertheless marked the latest example of Western countries — notably excluding the US — banding together in sometimes informal groupings on issues ranging from support for Ukraine to trade. — Prashant Rao, semafor.com, 9 Sep. 2026 See All Example Sentences for informal

Recent Examples of Synonyms for informal

Adjective

From the start, Paul’s unconventional and volatile romantic relationships were central to the series.

— Tracy Brown, Los Angeles Times, 15 Sep. 2026
Nobody lives here permanently—only rotating teams of scientists, engineers, and unconventional travelers.

— Hana Al-Khodairi, Condé Nast Traveler, 15 Sep. 2026

Definition of unconventional

Adjective

Garten sported hers buttoned up over a sleek pair of black tapered trousers while Gaines went more casual, with a distressed version and a matching pair of wide-leg jeans for a Canadian tuxedo vibe.

— Shea Simmons, PEOPLE, 5 Sep. 2026
The casual restaurants serving simple, inexpensive meals, typically at a lunch counter, began emerging in the late 19th century.

— Teresa Mull, FOXNews.com, 5 Sep. 2026

Definition of casual

Adjective

The colloquial names are fun, but can be confusing, because there’s also a plant called brown-eyed Susan, which is different from the black-eyed Susan.

— Sheryl DeVore, Chicago Tribune, 15 Sep. 2026
Silent sleep apnea is a colloquial term for the form of the condition that occurs without the loud, disruptive snoring most people associate with it.

— Hanna Wickes, Miami Herald, 4 Aug. 2026

Definition of colloquial

Adjective

On the one hand, there’s a fascination with collective joy and the forms of vernacular invention that aspire to it; on the other, there’s an underlying melancholy that points to the inevitability of isolation, an epistemology of loneliness.

— Pablo Larios, Artforum, 1 Sep. 2026
Undaunted, the couple embarked on a renovation, working with a local builder and an architect who understood the rustic vernacular architecture associated with Glacier National Park.

— Abby Montanez, Robb Report, 24 Aug. 2026