GNU Collaborative International Dictionary of English

Found 2 definitions

1.       
   Vernacular , a. [L. vernaculus born in one's house, native, fr. verna a slave born in his master's house, a native, probably akin to Skr. vas to dwell, E. was.] Belonging to the country of one's birth; one's own by birth or nature; native; indigenous; -- now used chiefly of language; as, English is our vernacular language. “A vernacular disease.” 
   Harvey.
   
   1913 Webster
   His skill in the vernacular dialect of the Celtic tongue.
   Fuller.
   
   1913 Webster
   Which in our vernacular idiom may be thus interpreted.
   Pope.
   
   1913 Webster
   
         
       

2.       
   Vernacular, n. The vernacular language; one's mother tongue; often, the common forms of expression in a particular locality, opposed to literary or learned forms.
   1913 Webster
    + 
   PJC