calx

n. lime

Calx is a residual substance, sometimes in the form of a fine powder, that is left when a metal or mineral combusts or is calcinated due to heat.Calx, especially of a metal, is now known as an oxide. According to the obsolete phlogiston theory, the calx was the true elemental substance, having lost its phlogiston in the process of combustion."Calx" is also sometimes used in older texts on artist's techniques to mean calcium oxide.
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Noun
1. a white crystalline oxide used in the production of calcium hydroxide
(synonym) calcium oxide, quicklime, lime, calcined lime, fluxing lime, unslaked lime, burnt lime
(hypernym) oxide
(substance-meronym) calcium, Ca, atomic number 20

(n.)
The substance which remains when a metal or mineral has been subjected to calcination or combustion by heat, and which is, or may be, reduced to a fine powder.
  

(n.)
Quicklime.
  

(n.)
Broken and refuse glass, returned to the post.
  

N C
limestone| lime; chalk| goal| goal-line (chalk mark)| end of life; game piece