CALX
Etymology
Noun
calx (plural calxes or calces)
(now, chiefly, historical) The substance which remains after a metal or mineral has been thoroughly burnt, once seen as being the essential substance left after the expulsion of phlogiston, but now recognised as being the metallic oxide (or, in some cases, the metal in a state of sublimation).
In the Eton College wall game, an area at the end of the field where a shy can be scored by lifting the ball against the wall with one's foot.
Source: Wiktionary
Calx, n.; pl. E. Calxes, L. Calces. Etym: [L. Calx, calcis.
limestone; cf. Gr. carraic rock Gael. carraig, W. careg, stone. Cf.
Chalk.]
1. (Chem.)
(a) Quicklime. [Obs.]
(b) 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.
Note: Metallic calxes are now called oxides.
2. Broken and refuse glass, returned to the post.
Source: Webster’s Unabridged Dictionary 1913 Edition