Emily Dickinson Lexicon

VER-NAC'U-LAR, a. [L. vernaculus, born in one's house, from verna, a servant.]

1. Native; belonging to the country of one's birth. English is our vernacular language. The vernacular idiom is seldom perfectly acquired by foreigners.
2. Native; belonging to the person by birth or nature. – Milner. A vernacular disease, is one which prevails in a particular country or district; more generally called endermic.