natation(n = noun.act) floating - the act of someone who floats on the water;
is a kind of swim, swimming
has particulars: dead-man's float, prone float

   The act of floating on the water; swimming. Sir T. Browne. [1913 Webster]

natation, n. formal or literary the act or art of swimming.

Etymology:
L natatio f. natare swim

N  navigation, aquatics, boating, yachting, ship, oar, paddle, screw, sail, canvas, aileron, natation, swimming, fin, flipper, fish's tail, aerostation, aerostatics, aeronautics, balloonery, balloon, ballooning, aviation, airmanship, flying, flight, volitation, wing, pinion, rocketry, space travel, astronautics, orbital mechanics, orbiting, voyage, sail, cruise, passage, circumnavigation, periplus, headway, sternway, leeway, fairway, mariner, flight, trip, shuttle, run, airlift, sailing, volant, aerostatic, seafaring, nautical, maritime, naval, seagoing, coasting, afloat, navigable, aerial, aeronautic, grallatory, under way, under sail, under canvas, under steam, on the wing, in flight, in orbit, bon voyage, spread the thin oar and catch the driving gale.