unidiomatic
adjective
un·id·i·o·mat·ic ˌən-ˌi-dē-ə-ˈma-tik 
: not conforming to established or accepted idiom : not idiomatic
unidiomatic language
a wordy and unidiomatic expression
unidiomatically
ˌən-ˌi-dē-ə-ˈma-ti-k(ə-)lē
adverb 
Word History
First Known Use
circa 1822, in the meaning defined above
unidiomatic
adjective
as in ungrammatical
Synonyms & Similar Words
Relevance
- ungrammatical
- nonstandard
- substandard
- illiterate
Antonyms & Near Antonyms
- grammatical
- idiomatic