potash

Etymology

Calque of Dutch potas, coined in 1598, equivalent to pot + ash. The literal translation is “pot ash”, because it was made by burning wood to ashes in a large pot. First attested in 1648. Doublet of potassium and potassa.

noun

1. The water-soluble part of the ash formed by burning plant material; used for making soap and glass and as a fertilizer.
2. (chemistry) An impure form of potassium carbonate (K₂CO₃) mixed with other potassium salts.
3. (chemistry, archaic) Potassium. Chiefly used in the names of compounds of the form "... of potash".
   permanganate of potash ― potassium permanganate
4. A class of potassium minerals, of similar applicability to potassium carbonate, such as being a fertilizer. (ie. potassium chloride, potassium hydroxide)

verb

1. To treat with potassium.
   In order to ascertain the difference between the rapidity of pickling when the tin frames had been potashed and pickling without such treatment, two batches were used. 1910, Platers' Guide: With which is Combined Brass World
   Gold ornaments are sand blasted or steel brushed nicely, then potashed, 1915, Metal Finishing: Preparation, Electroplating, Coating
   After removal from a worker bee they should be potashed in ten percent potassium hydroxide, washed, dehydrated, cleared, and mounted. 1953, Nature Magazine, page 223
   For the extraction of the internal sclerites the aedeagus was potashed in cold saturated KOH solution for several hours and transferred to a vial of distilled water. 2003, Senckenbergiana biologica, page 136