acid-fast

Definitions

  • WordNet 3.6
    • adj acid-fast not easily decolorized by acid solutions; pertains to micro-organisms (especially the tubercle bacillus that causes tuberculosis)
    • ***
Century Dictionary and Cyclopedia
    • acid-fast A literal translation of the German “säurfest”: applied to a class of bacteria which, when once stained with basic aniline dyes, tenaciously hold the dye on subsequent exposure to acids or alcohol. The most notable representative of this group is the tubercle bacillus, and its recognition in the tissues, the sputum, etc., is essentially based upon this “acid-fastness.”
    • ***

Usage

In literature:

Among the "acid oranges and yellows," we also find a goodly number which are of medium fastness.
"Scientific American Supplement, No. 810, July 11, 1891" by Various
The lactic acid buttermilk can be obtained from any good dairy and should be taken in the morning fasting and at bedtime.
"The Healthy Life, Vol. V, Nos. 24-28" by Various
Fastness to acids and fastness to alkalies is observed while carrying out the various acid and alkali tests given above.
"The Dyeing of Woollen Fabrics" by Franklin Beech
Finally, if the mixture is now heated above the boiling point of nitric acid, the acid distills away as fast as it is formed.
"An Elementary Study of Chemistry" by William McPherson
Fastness to acids and fastness to alkalies is observed while carrying out the various acid and alkali tests given above.
"The Dyeing of Cotton Fabrics" by Franklin Beech
This acid diffuses into the electrolyte as fast as the amount of sulphate will permit.
"The Automobile Storage Battery" by O. A. Witte
The acid radical has travelled twice as fast as the metal.
"The Mechanism of Life" by Stéphane Leduc
The fastness of the dyed colours to light, milling and acid satisfy the highest requirements.
"Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 8" by Various
The cheese-maker can determine rather accurately how fast the acid will develop during the ripening of the milk.
"The Book of Cheese" by Charles Thom and Walter Warner Fisk
***

In news:

Almost all people with gout have too much uric acid in their bodies, and the kidneys can't process this waste product fast enough.
Both combine proprietary strains of lactic acid bacteria with enzymes for fast ensiling and aerobic stability.
***