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frilled lizard

noun

a medium-sized Australian lizard, Chlamydosaurus kingi, having a large, cloaklike flap of skin on the neck that stiffens during courtship or threat displays, forming a wide ruff.

Origin of frilled lizard

First recorded in 1860–65; frill + -ed3
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019