Why is the ninth month called September?
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" (see exceed). As an adjective from late 15c.
excess ex·cess (ĭk-sěs', ěk'sěs')
An amount or quantity beyond what is normal or sufficient; a surplus.