psy·dra·cium \sīˈdrāsh(ē)əm\noun (pluralpsydra·cia \-)ə\) Etymology: New Latin, from Greek psydrakion, from psydrak- psydrax blister on the tongue (from psydros lying, untrue, from pseudein to lie, falsify) + -ion (n. suffix) archaic: pimple, pustule