Any of the Dinosauria, formerly known as Ornithoscelida.(noun)
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Use "ornithoscelidan" in a sentence
"On comparing the pelvis and hind limb of the ornithoscelidan with that of the crocodile, on the one side, and that of the bird, on the other"
"In Fig. 6, the pelvis and hind limbs of a crocodile, a three-toed bird, and an ornithoscelidan are represented side by side; and, for facility of comparison, in corresponding positions; but it must be recollected that, while the position of the bird's limb is natural, that of the crocodile is not so."
"In fact, the ornithoscelidan limb is comparable to that of an unhatched chick."