sə̇ˈnägnəthəs, sīˈ- noun
Usage: capitalized
Etymology: New Latin, from cyn- + -gnathus -gnathous
: a genus of large carnivorous therapsid reptiles (suborder Theriodontia) that greatly resembled mammals in form, were presumably near the direct ancestral line of the true mammals, and are known chiefly from remains found in the Karroo formation of the Triassic