chelonian UK /kɪˈləʊ.ni.ən/US /kɪˈloʊ.ni.ən/adjective 1noun 1forms 3 adjective1 •Of, relating to, or belonging to the order Chelonia (Testudines), which includes the turtles and tortoises. noun1 •A reptile of the order Chelonia (Testudines). formschelonians · more chelonian · most chelonian
