ungrammatical

[ uhn-gruh-mat-i-kuh l ]

/ ˌʌn grəˈmæt ɪ kəl /

grammatically incorrect or awkward; not conforming to the rules or principles of grammar or accepted usage: an ungrammatical sentence.

Origin of ungrammatical

First recorded in 1645–55; un-¹ + grammatical

un·gram·mat·i·cal·ly, adverb

Note, however the fine roof, old brass lectern with ungrammatical inscription, 16th-cent.

Somerset |G.W. Wade and J.H. Wade
Do not use a verb, conjunction, preposition, or noun in a double capacity when one of the uses is ungrammatical.

The Century Handbook of Writing |Garland Greever
The 'burden pure have been' certainly was a misprint, as certainly 'nor man nor nature satisfy' is ungrammatical.

The Letters of Elizabeth Barrett Browning (1 of 2) |Frederic G. Kenyon
He would also criticize my conversation, never letting one word pass that was ungrammatical or incorrectly pronounced.

Memories and Anecdotes |Kate Sanborn

"He was talkin' about cavvs," said the feller, whose name was Reddy—a most ungrammatical cuss.

Yellowstone Nights |Herbert Quick

ungrammatical

/ (ˌʌnɡrəˈmætɪkəl) /

(of a sentence) not regarded as correct by native speakers of the language