What is the part that holds the lampshade called?

The part that holds the lampshade is called a fitter. Easy to identify by its three legs, the spider fitter is the most common type and works by fitting over a U-shaped wire on the top of a lamp called a harp. Shades for lamps that lack harps will have other types of fitters. Circular UNO fitters hug the lamp socket with a pressure fitting, while euro fitters screw onto the lamp socket. Clip-on fittings consist of two U-shaped wires that hug a lamp's light bulb. Shop a diverse assortment of lamps and lampshades on 1stDibs.