before vowels pter-, word-forming element in science meaning "feather; wing," from Greek pteron "wing," from PIE *pt-ero- (source also of Sanskrit patram "wing, feather," Old Church Slavonic pero "pen," Old Norse fjöðr, Old English feðer), from root *pet- "to rush; to fly."
psychrometer
psychrophobia
pt-
ptarmic
ptarmigan
ptero-
pterodactyl
Ptolemaic
Ptolemy
ptomaine
ptosis