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Webster 1913 Edition
Sauropterygia
‖
Sau-ropˊte-ryg′i-a
,Noun.
 pl.
 [NL., fr. Gr. [GREEK] a lizard + [GREEK], [GREEK], a wing.] 
(Paleon.) 
Same as 
Plesiosauria
. Definition 2025
Sauropterygia
Sauropterygia
Translingual
Proper noun
†Sauropterygia
- A taxonomic superorder within the class Reptilia – extinct taxon of aquatic reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Mesozoic before they became extinct at the end of that era. They are united by a radical adaptation of their pectoral girdle, designed to support powerful flipper strokes.