blue john


Definition of blue john

  1. 1 :  a fibrous or columnar variety of fluorite found in Derbyshire, England and used especially for vases

  2. 2 sometimes capitalized J, dialectal :  skim milk; especially :  milk that is just beginning to sour

Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Join MWU now and get access to America’s largest dictionary, with:

  • 300,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

Origin and Etymology of blue john

from the name John

Seen and Heard

What made you want to look up blue john? Please tell us where you read or heard it (including the quote, if possible).


a rounded knoll or a ridge of ice

Get Word of the Day daily email!