Imperishable \Im*per"ish*a*ble\, a. [Pref. im- not + perishable: cf. F. imp['e]rissable.] Not perishable; not subject to decay; indestructible; enduring permanently; as, an imperishable monument; imperishable renown. -- {Im*per"ish*a*ble*ness}, n. -- {Im*per"ish*a*bly}, adv.