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

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of informal The mood was informal and chatty; Weyers and another member ate takeout noodles. — Shayla Love, New Yorker, 10 Oct. 2026 Slota’s prosecution is the latest linked to an informal but growing gun fandom on the far Left. — Hudson Crozier, The Washington Examiner, 9 Oct. 2026 The mayor and village trustees’ comments came late Monday during their first public review of a project years in the making — albeit an informal, early evaluation, as plans now face further revisions. — Christopher Placek, Chicago Tribune, 8 Oct. 2026 Keshani, who is serving a five-year sentence, pushed for an informal wedding Sunday as fears mounted that Sepahi’s execution was imminent after a final family summons. — Emma Bussey, FOXNews.com, 8 Oct. 2026 See All Example Sentences for informal

Recent Examples of Synonyms for informal

Adjective

The food-beauty collaboration pipeline is gaining an unconventional contender.

— Noor Lobad, Footwear News, 15 Oct. 2026
The most unconventional of the trio is the jamón y queso, built with ribbons of jamón serrano.

— Jenn Harris, Los Angeles Times, 15 Oct. 2026

Definition of unconventional

Adjective

This most recent collection from McCartney features a massive array of differing styles ranging from casual to chic and formal, with Stern’s choice of the elegant bodice an excellent one for the Albie Awards.

— Erin Wisti, Footwear News, 10 Oct. 2026
Physicality presents technical challenges to audio recording, and wit—primarily achievable by coming up with lots of ideas in advance—quickly becomes alienating in a casual setting.

— Dan Brooks, New Yorker, 10 Oct. 2026

Definition of casual

Adjective

The theme uses a colloquial phrase almost like a mathematical function.

— Sam Corbin, New York Times, 7 Oct. 2026
Years later in an interview with NPR, Díaz discussed his efforts to blend formal Dominican Spanish, colloquial Spanish, pop culture references, and everyday American speech into his narrative.

— Britannica Editors, Encyclopedia Britannica, 7 Oct. 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