a. and sb. [ad. L. subacidus: see SUB- 20 b and ACID. Cf. It., Sp. subacido.]
A. adj. 1. Somewhat or moderately acid.
1669. W. Simpson, Hydrol. Chym., 328. It weeps forth a subacid liquor in great abundance.
1676. Grew, Anat. Plants, Lect. ii. (1682), 244. Mercury, with Oyl of Vitriol, will not stir, nor with Oyl of Sulphur. But with Spirit of Nitre presently boyls up. Hence Mercury is a subacid Metal.
1725. Bradley’s Fam. Dict., s.v. Sallet, The sub-acid Orange, sharpens the Appetite.
1732. Arbuthnot, Rules of Diet, in Aliments, etc. (1736), 254. All Fruits which contain a subacid essential salt.
1836. Landor, Pericles & Aspasia, Wks. 1846, II. 385. He enjoys a little wine after dinner, preferring the lighter and subacid.
1891. S. C. Scrivener, Our Fields & Cities, 150. The food of the human being cannot be ‘suitable’ unless varied by sub-acid substances of some kind.
b. Chem. Containing less than the normal proportion of acid.
1855. J. Scoffern, in Orr’s Circ. Sci., Elem. Chem., 38. With regard to neutral and superacid, or subacid, salts.
2. Of character, temper, speech, etc.: Somewhat acid or tart; verging on acidity or tartness.
1765. Sterne, Tr. Shandy, VIII. xxvi. From a little subacid kind of drollish impatience in his nature, he would never submit to it.
1811. Syd. Smith, Wks. (1867), I. 205. A stern subacid Dissenter.
1829. Scott, Antiq., Advert. ¶ 7. An excellent temper, with a slight degree of subacid humour.
1876. W. Clark Russell, Is he the Man? II. 203. A hard, subacid expression … modified the character of her beauty.
1883. Mrs. H. Ward, Robt. Elsmere, 428. Rose … was always ready to make him the target of a sub-acid raillery.
B. sb. 1. Subacid quality or flavor, subacidity.
1838. Ticknor, Life, Lett. & Jrnls., II. viii. 145. Rogers … talked in his quiet way…, showing sometimes a little subacid.
1840. Hood, Up the Rhine, 198. You will perceive a little sub-acid in Markham’s statement.
1884. E. P. Roe, in Harper’s Mag., July, 241/1. The subacid of the strawberry seemed to furnish the very tonic she needed.
2. A subacid substance.
1828–32. Webster, Subacid, a substance moderately acid.
1891. S. C. Scrivener, Our Fields & Cities, 150. Sub-acids in their most convenient form cannot be put into a pill box.
Hence Subacidity, the quality or condition of being subacid; also, something slightly acid.
1833. Carlyle, Misc. Ess., Diderot (1888), V. 38. There is certain sardonic subacidity in Père Hoop.
1886. Law Jrnl., 16 Jan., 37/2. The subacidity which gives special flavour to his style.
