The building blocks of English

Affixes

-gnomy

Knowledge.

Greek gnōmē, an opinion or maxim.

The only common word in this form is physiognomy, a person's facial features, especially as a guide to character or origin. Rarer examples include chirognomy (Greek kheir, hand), the art of estimating character by inspecting the hand, and craniognomy, the study of the form and character of the skull.