Illimitable \Il*lim"it*a*ble\, a. [Pref. il- not + limitable: cf. F. illimitable.] Incapable of being limited or bounded; immeasurable; limitless; boundless; as, illimitable space. The wild, the irregular, the illimitable, and the luxuriant, have their appropriate force of beauty. --De Quincey. Syn: Boundless; limitless; unlimited; unbounded; immeasurable; infinite; immense; vast. -- {Il*lim"it*a*ble*ness}, n. -- {Il*lim"it*a*bly}, adv.