What does vernacular mean?

ver•nac•u•larPronunciation: (vur-nak'yu-lur, vu-nak'-), [key] —adj. 1. (of language) native or indigenous (opposed to literary or learned). 2. expressed or written in the native language of a place, as literary works: a vernacular poem. 3. using such a language: a vernacular speaker. 4. of or pertaining to such a language. 5. using plain, everyday, ordinary language. 6. of, pertaining to, or characteristic of architectural vernacular. 7. noting or pertaining to the common name for a plant or animal. 8. Obs.(of a disease) endemic. —n. 1. the native speech or language of a place. 2. the language or vocabulary peculiar to a class or profession. 3. a vernacular word or expression. 4. the plain variety of language in everyday use by ordinary people. 5. the common name of an animal or plant as distinguished from its Latin scientific name. 6. a style of architecture exemplifying the commonest techniques, decorative features, and materials of a particular historical period, region, or group of people. 7. any medium or mode of expression that reflects popular taste or indigenous styles.