The Collaborative International Dictionary
Potash \Pot"ash`\, n. [Pot + ash.] (Chem.)
The hydroxide of potassium hydrate, a hard white brittle substance, KOH, having strong caustic and alkaline properties; -- hence called also caustic potash.
The impure potassium carbonate obtained by leaching wood ashes, either as a strong solution (lye), or as a white crystalline (pearlash).
Potassa \Po*tas"sa\, n. [NL., fr. E. potash.] (Chem.)
Potassium oxide. [Obs.]
Potassium hydroxide, commonly called caustic potash.
Wiktionary
n. (context dated English) potassium hydroxide.
WordNet
n. a potassium compound often used in agriculture and industry [syn: potash, potassium hydroxide]
Usage examples of "caustic potash".
These two layers are sometimes well seen when a gland has been crushed or boiled in caustic potash.
To absorb it, it was necessary to fill some jars with caustic potash, and to shake them incessantly.
Would he obtain air by chemical means, in getting by heat the oxygen contained in chlorate of potash, and in absorbing carbonic acid by caustic potash?