alkalis
plural of alkali
Source: Wiktionary
Al"ka*li, n.; pl. Alkalis or Alkalies. Etym: [F. alcali, ultimately fr. Ar. alqali ashes of the plant saltwort, fr. qalay to roast in a pan, fry.]
1. Soda ash; caustic soda, caustic potash, etc.
2. (Chem.)
Definition: One of a class of caustic bases, such as soda, potash, ammoma, and lithia, whose distinguishing peculiarities are solubility in alcohol and water, uniting with oils and fats to form soap, neutralizing and forming salts with acids, turning to brown several vegetable yellows, and changing reddened litmus to blue. Fixed alkalies, potash and soda.
– Vegetable alkalies. Same as Alkaloids.
– Volatile alkali, ammonia, so called in distinction from the fixed alkalies.
Source: Webster’s Unabridged Dictionary 1913 Edition
14 April 2025
(noun) maximum clarity or distinctness of an image rendered by an optical system; “in focus”; “out of focus”
The first coffee-house in Mecca dates back to the 1510s. The beverage was in Turkey by the 1530s. It appeared in Europe circa 1515-1519 and was introduced to England by 1650. By 1675 the country had more than 3,000 coffee houses, and coffee had replaced beer as a breakfast drink.
