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 Comparative data on long prison terms is thin, but there is consensus, if informal, that Smith has the American record. — Edmund H. Mahony, Hartford Courant, 19 July 2026 The poor air quality, which is dangerous for both players and fans, led FIFA and the White House to hold informal discussions over moving the World Cup final. — Kevin Baxter, Los Angeles Times, 18 July 2026 For the dozens of NHL, minor league and college players who make their off-season homes in Minnesota, informal morning skates at various arenas throughout the Twin Cities have been going on for decades. — Jess Myers, Twin Cities, 17 July 2026 That follows informal discussions between FIFA and World Cup task force CEO Andrew Giuliani over the matter. — Leon Imber, New York Times, 17 July 2026 See All Example Sentences for informal

Recent Examples of Synonyms for informal

Adjective

Built to supply water to the surrounding area, the structure was transformed into a private residence in the early 1980s by local architect Doug Rucker who embraced its unconventional shape rather than alter it.

— Abby Montanez, Robb Report, 18 July 2026
The development is a significant step toward expanding future nuclear fuel supply through unconventional uranium resources.

— Prabhat Ranjan Mishra, Interesting Engineering, 18 July 2026

Definition of unconventional

Adjective

The messages were casual, sly, a little irreverent—proof that Google wasn’t like any other company—while always amplifying the corporate mythology.

— Claire Stapleton, New Yorker, 18 July 2026
Try this formula for a low-key coffee date, a day of shopping, or a casual swing by the office.

— Kelsey Stewart, Glamour, 18 July 2026

Definition of casual

Adjective

Its name refers to the colloquial term once used for Papaya—paw-paw.

— Kelsey Glennon, Southern Living, 30 May 2026
The Solons name refers to an ancient Greek lawmaker, whose name later became a colloquial term for wise legislators, according to the Merriam-Webster dictionary.

— Camila Pedrosa, Sacbee.com, 29 May 2026

Definition of colloquial

Adjective

Screenplay credits are shared by Damodaran, Joses Imona, and Jennifer Litau, with Litau also handling Tok Pisin and vernacular-language translation duties.

— Naman Ramachandran, Variety, 17 July 2026
Compiled in 1964 by Elektra Records founder Jac Holzman, this four-LP, 83-track box set was intended as an accessible survey of the roots and branches of American vernacular music.

— Ted Olson, The Conversation, 2 July 2026