Synonyms of idiomatic
nativeYour native language or tongue is the first language that you learned to speak when you were a child.
• French is not my native tongue.
vernacularVernacular architecture is the style of architecture in which ordinary people's houses are built in a particular region.
• dialects such as black vernacular English
Thesaurus for idiomatic from the Collins English Thesaurus
Idiomatic language uses words in a way that sounds natural to native speakers of the language.