A retainer having an annular body with a plurality of pockets. Each pocket has a pair of corner portions that form an opening. The pockets have a spherical inside surface and a pair of tapered surfaces. Alternatively, the pockets can have a spherical inside surface and at least two pairs of tapered surfaces. The geometry of the pockets including the corner portions has rotational symmetry. The retainer improves lubricant retention, and reduces vibration, noise and non-repeating run out.