The Collaborative International Dictionary
Ornithoscelidan
Ornithoscelida \Or*ni`tho*scel"i*da\, n. pl. [NL., fr. Gr. 'o`rnis, 'o`rniqos, a bird + ? a leg.] (Zo["o]l.) A group of extinct Reptilia, intermediate in structure (especially with regard to the pelvis) between reptiles and birds. -- Or`ni*tho*scel"i*dan, a.
Wiktionary
ornithoscelidan
n. (context zoology now historical English) Any of the Dinosauria, formerly known as ''(taxlink Ornithoscelida order noshow=1)''.