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Any of various herbivorous ornithiscian dinosaurs of the group Marginocephalia of the Cretaceous Period, characterized by a bony shelf or frill at the back of the skull and including the ceratopsians and the pachycephalosaurians.

[From New Latin Marginocephalia, group name : Latin margō, margin-, margin; see margin + Greek kephalē, head; see cephalic.]

mar′gi·no·ce·phal′i·an adj.
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.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.marginocephalian - includes boneheaded (pachycephalosaurs) and horned (ceratopsian) dinosaursmarginocephalian - includes boneheaded (pachycephalosaurs) and horned (ceratopsian) dinosaurs
animal order - the order of animals
order Ornithischia, Ornithischia - extinct terrestrial reptiles having bird-like pelvises: armored dinosaurs (thyreophorans); boneheaded and horned dinosaurs (marginocephalians); duck-billed dinosaurs (euronithopods)
suborder Pachycephalosaurus - boneheaded dinosaurs; late Cretaceous
Ceratopsia, suborder Ceratopsia - horned dinosaurs
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.