physiognomy (n.)

late 14c., phisonomie, "art of judging characters from facial features," from Old French fisonomie, phizonomie and directly from Medieval Latin physonomia, from Late Latin physiognomia, from Greek physiognōmia "the judging of a person's nature by his features," from physio- (see physio-) + gnōmōn (genitive gnōmōnos) "a judge, interpreter, indicator" (from PIE root *gno- "to know"). The meaning "face, countenance, the human face and its expressions" is from c. 1400. Related: Physiognomical.