rhynchocephalian
noun
rhyn·cho·ce·pha·lian ˌriŋ-kō-sə-ˈfāl-yən 
: any of an order (Rhynchocephalia) of reptiles resembling lizards that includes the tuatara as the only living member
rhynchocephalian adjective
Word History
Etymology
ultimately from Greek rhynchos beak, snout + kephalē head — more at cephalic
First Known Use
1886, in the meaning defined above