1Relating to or denoting the second period of the Paleozoic era, between the Cambrian and Silurian periods.
- ‘In contrast, the Ordovician magmatic event postdates the pre-Variscan deformation in the external zone.’
- ‘They interpreted these dates to represent an Ordovician regional metamorphic event.’
- ‘These are overlain by low-grade metamorphosed sediments and volcanics of Ordovician and Silurian age.’
- ‘Because of the disparate nature of the Ordovician and Cambrian records, it is difficult to make direct comparison between the two events.’
- ‘Additional indications for a potential tectonic boundary in Hinnoy are provided by local evidence of an Ordovician event in basement units of the Lofoten area.’
- 1.1The Ordovician period or the system of rocks deposited during it.
Late 19th century: from Ordovices, the Latin name of an ancient British tribe in North Wales, + -ian.