Webster's Revised Unabridged Dictionary · 1913

Mesozoic

Mesozoic , adjective

[Meso- + Greek {not transcribed} life, from {not transcribed} to live.]

(Geology) Belonging, or relating, to the secondary or reptilian age, or the era between the Paleozoic and Cenozoic. See Chart of Geology.

Mesozoic , noun

The Mesozoic age or formation.