Calx n. : Quicklime.

Calx 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.

Calx n. : Broken and refuse glass, returned to the post.

Example:
Chemistry Homwork dealing with Calx, empirical formula and phlogiston?

Taxonomy
Cal Expo, Horse Racing, Super High, High-5, Superfectas, POST-TIME, incentive programs, Wine, 50 Cent, Clubhouse Dining Room, Thunder, layoff, Cherry Tree, Luke, Franco, Smoothie, CHHA, Racing.

Defination from the web:
... Thunder Seelster Wins With A Bang ...