Since I know I'm not the only one that had to look it up:
A blisk (or bladed disk) is a single engine component consisting of a rotor disk and blades, which may be either integrally cast, machined from a solid piece of material, or made by welding individual blades to the rotor disk. The term is used mainly in aerospace engine design. The word is a portmanteau of blade and disk, the two components it replaces in turbomachinery. Blisks may also be known as integrally bladed rotors (IBR).