Jurassic

1. n. The Jurassic period or formation; — called also the Jura.
2. a. Of the age of the middle Mesozoic, including, as divided in England and Europe, the Lias, Oolite, and Wealden; — named from certain rocks of the Jura mountains.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.