Synonyms of ungrammatical

ungrammatical

adjective

ˌən-grə-ˈma-ti-kəl 

as in illiterate

violating approved patterns of speaking and writing

the résumé and its ungrammatical cover letter were summarily thrown in the trash

Synonyms & Similar Words

• illiterate
• unidiomatic
• substandard
• nonstandard

Antonyms & Near Antonyms

• grammatical
• idiomatic

Example Sentences

Recent Examples of ungrammatical

The notes were vintage O’Keeffe—brief, vivid, enlightening, and, yes, often ungrammatical, but brilliantly so. — Calvin Tomkins, New Yorker, 15 Dec. 2025

But if language exemplifies the human capacity for internalizing grammatical conventions, then my moment of rule-breaking does not in fact expose some ungrammatical first nature. — Harmon Siegel, Artforum, 1 Oct. 2025

That could be useful for conversations where telegraphic, ungrammatical messages would come off as impolite. — Tom Simonite, Wired, 18 Oct. 2020

But to many Americans, the pronouns are ungrammatical and confusing. — Samantha Schmidt, Washington Post, 16 Aug. 2019

None of that here in the pretentious, inauthentic speech of an ungrammatical kid. — Toby Zinman, Philly.com, 11 June 2018

Yes, its ungrammatical slogan does not exactly roll off the tongue. — Mark Lisanti, Vanities, 11 May 2018