Definitions
from The Century Dictionary.
- noun The local name in Derbyshire, England, of a blue variety of fluorspar.
from the GNU version of the Collaborative International Dictionary of English.
- noun A name given to fluor spar in Derbyshire, where it is used for ornamental purposes.
Etymologies
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Examples
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I’d never heard of blue-john milk before reading about it here.
Hard at work in Seattle | The Blog of Michael R. Eades, M.D. 2009
ruzuzu commented on the word blue-john
See cand.
April 18, 2011