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Word of the Day
Thursday, March 07, 2013

Definitions for tertiary

  1. of the third order, rank, stage, formation, etc.; third.
  2. Chemistry. A. noting or containing a carbon atom united to three other carbon atoms. B. formed by replacement of three atoms or groups.
  3. (initial capital letter) Geology. noting or pertaining to the period forming the earlier part of the Cenozoic Era, occurring from 65 million to 2 million years ago, characterized by the development and proliferation of mammals.

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Citations for tertiary
For it was impossible not to be sensible, that, while these three characters figured so largely on my private theatre, I — though probably reckoned as a friend by all — was at best but a secondary or tertiary personage with either of them. Nathaniel Hawthorne, The Blithedale Romance, 1852
She'd explained all of this the last couple of days to various out-of-town cops who'd volunteered to take over the secondary and tertiary policing duties of the city. Jay McInerney, The Good Life, 2007
Origin of tertiary
1540-1550
Since entering English in the mid 1500s, tertiary, which comes from the Latin tertius meaning "third," has been applied as a technical term for many different subject matters.