"a going beyond ordinary, necessary, or proper limits; superfluity; undue indulgence of appetite, want of restraint in gratifying the desires; the amount by which one number or quantity exceeds another," late 14c., from Old French exces (14c.) "excess, extravagance, outrage," from Latin excessus "departure, a going beyond the bounds of reason or beyond the subject," from stem of excedere "to depart, go beyond," from ex "out" (see ex-) + cedere "to go, yield" (from PIE root *ked- "to go, yield"). As an adjective, "beyond what is necessary, proper, or right," from late 15c.