acidic, a. Min.
(əˈsɪdɪk)
[f. acid + -ic.]
1. Applied by Dana to that element in a ternary compound mineral, which forms an oxygen, sulphur, or other salt, with a basic element; e.g. the silicon in silicate of lime. See quotation under acidific.
| 1880 Dana Mineral. Introd. 16 In some classes of compounds only part of the oxygen serves to unite the acidic element to the basic. |
2. Abounding in an acidic element, usually silicon.
| 1877 Green Phys. Geol. ii. §5. 47 So the Crystalline rocks can be divided..into the Highly Silicated or Acidic rocks. 1878 Lawrence tr. Cotta, Rocks Classified 120 The acidic rocks..are distinguished by a felspar richer in silica. 1879 Rutley Study of Rocks iv. 34 Both acidic and basic rocks are known in some instances to have emanated, etc. |
3. Of, pertaining to, or of the nature of, an acid. Also fig.
| 1889 in Cent. Dict. 1905 Harmsworth Encycl. II. 1162/2 Though neutral to litmus, carbon disulphide exhibits some acidic properties, uniting with alkaline sulphides to form sulpho-carbonates. 1961 John O'London's 21 Dec. 678/3 Starkly etched portraits of immigrants in New York heat⁓wave, doom-laden acidic. |