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Related to pelycosaur: therapsid, edaphosaurus


Any of various extinct, chiefly carnivorous synapsids of the Carboniferous and Permian Periods, including the dimetrodon and other species with saillike structures along the back.

[New Latin Pelycosauria, name of the former suborder in which the various pelycosaurs were classified : Greek pelux, peluk-, bowl, cup (from the typical shape of the ischium ) + Greek sauros, lizard.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Palaeontology) any extinct mammal-like reptile of the order Pelycosauria, of Upper Carboniferous to Lower Permian times, from which the therapsids are thought to have evolved
[C19: from New Latin Pelycosauria, from Greek pelyx bowl, pelvis, + -saur]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pelycosaur - large primitive reptile having a tall spinal sail; of the Permian or late Paleozoic in Europe and North America
synapsid, synapsid reptile - extinct reptile having a single pair of lateral temporal openings in the skull
order Pelycosauria, Pelycosauria - edaphosaurus; dimetrodon
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
(3) A metatarsal possibly of Trichasaurus, a caseid pelycosaur from the Leonardian of Texas.
Also skipping the sand dunes was Pelycosaur Ophiacodon, a flesh-eating reptile-cum-mammal, again only found in this county.
A thermal model of the sailback pelycosaur. Paleobiology 12:450-458.