1682 N. Grew Exper. Luctation ii. ii. §46 in 247 Spirit of Salt is a subalkaline Acid.
1759 R. Dossie I. 267 The subalkaline salts are, such as are formed by the combination of subacid salts with alkaline salts.
1847 J. F. Royle 108 Taste sweetish, a little styptic, and subalkaline.
1979 R. Anderton et al. xii. 167/1 All the basaltic units are tholeiitic or subalkaline.
2002 43 1936/1 In the sub-alkaline basalt suite, Sr, Nd and Pb isotopic ratios covary with major elements.