Invincible \In*vin"ci*ble\, a. [L. invincibilis: cf. F. invincible. See {In-} not, and {Vincible}.] Incapable of being conquered, overcome, or subdued; unconquerable; insuperable; as, an invincible army, or obstacle. Lead forth to battle these my sons Invincible. --Milton. -- {In*vin"ci*ble*ness}, n. -- {In*vin"ci*bly}, adv.