from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of, belonging to, or designating the era of geologic time that includes the Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, and Permian periods and is characterized by the appearance of marine invertebrates, primitive fishes, land plants, and primitive reptiles. See Table at geologic time.
- n. The Paleozoic Era.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Of a geologic era within the Phanerozoic eon that comprises the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian periods from about 542 to 250 million years ago, from the age of trilobites to that of reptiles.
- proper n. The Paleozoic era.
from the GNU version of the Collaborative International Dictionary of English
- adj. Of or pertaining to, or designating, the older division of geological time during which life is known to have existed, including the Silurian, Devonian, and Carboniferous ages, and also to the life or rocks of those ages. See Chart of geology.
- n. The Paleozoic time or strata.
from The Century Dictionary and Cyclopedia
- In geology, belonging to or constituting a geological formation characterized by the presence of ancient forms of life: applied to the oldest division of the geological series, beginning with the lowest stratified fossiliferous group, and extending upward to the base of the Triassic, or to the top of the Permian.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. from 544 million to about 230 million years ago
- adj. of or relating to or denoting the Paleozoic era
paleo- + -zoic (Wiktionary)