a. and sb. [ad. L. quaternāri-us, f. quaternī four together, by fours. Cf. F. quaternaire (1515).]
A. adj. 1. Consisting of four things or parts; characterized by the number four. Now chiefly Chem. in quaternary compound, a combination of four elements or radicals.
Quaternary number, usually = 4, but sometimes taken as = 10 (see B).
1605. Timme, Quersit., I. xi. 45. To appoynt a quaternarie number of elements, out of the quaternary number of the fower qualities.
1695. F. Gregory, Doctr. Trin., 63. We read what great respect Pythagoras and his Sect had for … their Quaternary number.
1825. T. Thomson, 1st Princ. Chem., I. 37. Ammonia is a quaternary compound, consisting of 1 atom azote and 3 atoms hydrogen.
1830. Lindley, Nat. Syst. Bot., 14. The quaternary number of the divisions of the flower.
1869. Oliver, Elem. Bot., I. ii. 17. The nitrogen occurs combined with the same three elements, forming a quaternary compound.
2. Geol. Used, with the sense of ‘fourth in order,’ as an epithet of the most recent of the geological periods (following on the Tertiary), and of the deposits, animals, etc., belonging to it.
1843. W. Humble, Dict. Geol., 216. Quaternary formations.
1865. Tylor, Early Hist. Man., viii. 198. The instruments of the Drift, or Quaternary deposits.
1871. Darwin, Desc. Man, I. vii. 237. The quaternary race of the caverns of Belgium.
1880. A. R. Wallace, Isl. Life, xxi. 448. Deposits which may be of Quaternary or even of Pliocene age.
B. sb. A set of four (things); the number four.
Quaternary of numbers, the Pythagorean τετρακτύς, or 1 + 2 + 3 + 4 = 10.
c. 1430. Art of Nombrynge (E.E.T.S.), 8. Withdraw ther-for the quaternary, of the article of his denominacion twies, of .40., And ther remaynethe .32.
1603. Holland, Plutarch’s Mor., 1310. The quaternarie is the first square or quadrate number.
a. 1638. Mede, Wks. (1672), 654. In which Quaternary of Kingdoms … the Roman, being the Last of the Four, is the Last Kingdom.
1661. Lovell, Hist. Anim. & Min., 438. According to quaternaries, or septenaries [of days] after the nature of the disease.
1809. W. Irving, Knickerb. (1861), 44. They are regarded with as much veneration as were the disciples of Pythagoras … when initiated into the sacred quaternary of numbers.
1845. Day, trans. Simon’s Anim. Chem., I. 141. Thus quaternary compounds may be split into several quaternaries with the same or a different radical.
