light, thin, and flimsy, tending to billow or float, usually describing fabric or clothing;
e.g. Her dress was made of floaty material that swirled around her as she walked.
(noun)
(informal, American) an inflatable object that floats in water, on which a person may sit and recline while floating, especially inflatable armbands that float and are thus worn by children to help them float and swim;
e.g. He was relaxing on a floaty in the middle of the swimming pool. One floaty slipped off her arm.