  We construct spinning dual M2 giant gravitons in AdS_4 x S^7, which
generically become 1/16 BPS states, and show that their world-volumes become
torii. By taking an orbifold, we obtain spinning dielectric D2-brane
configurations in AdS_4 x CP^3 dual to specific BPS operators in ABJM theory.
This reveals a novel mechanism how to give an angular momentum to a dielectric
D2-brane. We also find that when its angular momentum in the AdS_4 becomes
large, it approaches to a ring-like object. Our result might suggest an
existence of supersymmetric black rings in the AdS_4 background. We will also
discuss dual giant gravitons in AdS_4 x CP^3.
