diachronous, a.
(daɪˈækrənəs)
[f. as diachronic a.: see -ous.]
1. Geol. Exhibiting or characteristic of diachronism (see prec., sense 1); not of a uniform geological age.
| 1926 W. B. Wright in Rep. Brit. Assoc. 1926 355 The Haslingden Flag Marine Band was not contemporaneous in the north-east and south-west..analogous phenomena are demonstrable in almost every highly fossiliferous formation. It is now proposed to introduce the term diachronous to describe a bed having such relations to the zonal succession. 1929 L. J. Wills Physiographical Evol. Brit. xxiv. 322 The grit facies must therefore transgress the time-zones, i.e. the grits are diachronous. 1966 D. T. Donovan Stratigr. v. 125 There is a recurring tendency among stratigraphers to be alarmed when a formation is discovered to be diachronous. 1969 Proc. Geol. Soc. Lond. Aug. 146 Once the marker-points are adequately defined, subsequent demonstrations of facies-changes, diachronous boundaries, lacunae or similar phenomena do not affect their validity. |
2. Linguistics. = diachronic a. 2.
| 1936 English Studies XVIII. 93 Since de Saussure and Bally we have learnt to distinguish diachronous and synchronous linguistics. |