— acidly , adv. — acidness , n.
/as"id/ , n.
1. Chem. a compound usually having a sour taste and capable of neutralizing alkalis and reddening blue litmus paper, containing hydrogen that can be replaced by a metal or an electropositive group to form a salt, or containing an atom that can accept a pair of electrons from a base. Acids are proton donors that yield hydronium ions in water solution, or electron-pair acceptors that combine with electron-pair donors or bases.
2. a substance with a sour taste.
3. something, as a remark or piece of writing, that is sharp, sour, or ill-natured: His criticism was pure acid.
4. Slang. See LSD (def. 2).
5. put on the acid , Australian Slang. to importune someone, as for money, sexual favors, or confidential information.
adj.
6. Chem.
a. belonging or pertaining to acids or the anhydrides of acids.
b. having only a part of the hydrogen of an acid replaced by a metal or its equivalent: an acid phosphate.
c. having a pH value of less than 7. Cf. alkaline (def. 4).
7. sharp or biting to the taste; tasting like vinegar; sour: acid fruits.
8. sharp, biting, or ill-natured in mood, manner, etc.: an acid remark; an acid wit.
9. Geol. containing much silica.
10. Metall. noting, pertaining to, or made by a process in which the lining of the furnace, or the slag that is present, functions as an acid in high-temperature reactions in taking electrons from oxide ions: usually a siliceous material, as sand or ganister. Cf. basic (def. 3).
[ 1620-30; acidus sour, akin to acer sharp, acetum vinegar, ACESCENT, ACICULA ]
Syn. 8. acerbic, stinging, vitriolic, tart. ACID, ASTRINGENT are terms used figuratively of wit or humor. ACID suggests a sharp, biting, or ill-natured quality: an acid joke about an opponent. ASTRINGENT connotes severity but usually also a bracing quality, as of something applied with curative intent: astringent criticism.