The Collaborative International Dictionary of English v.0.48:
Irremovable \Ir`re*mov"a*ble\, a. Not removable; immovable; inflexible. --Shak. -- Ir`re*mov"a*bly, adv. [1913 Webster]WordNet (r) 3.0 (2006):
irremovable adj 1: incapable of being removed or away or dismiss; "irremovable boulders"; "irremovable obstacles" [ant: removable]