Definition from Wiktionary, the free dictionary
- Rhymes: -əʊtə(r)
floater (plural floaters)
- Agent noun of float; one who or that which floats.
- An employee of a company who does not have fixed tasks to do but fills in wherever needed, usually when someone else is away.
- A threadlike speck in the visual field that seems to move, possibly caused by degeneration of the vitreous humour.
- An "extra" male at a dinner party, or a young friend of the hostess, whose assignment is to entertain the female guests.
- (insurance) A policy covering property at more than one location or which may be in transit.
- (police jargon) A floating corpse picked up from a body of water.
- (sports) An unaffiliated player.
- (surfing) A maneuver in which a surfer transitions above the unbroken face of the wave onto the lip, or on top of the breaking section of the wave.
- (vulgar) A piece of faeces that floats.
- He left a floater in the toilet.
- (two-up) A coin which does not spin when thrown in the air.
- (slang) Someone who attaches themselves to a group of people, much to the dismay of that group, and repeatedly shows up to participate in group activities despite attempts to get rid of, or “flush,” that person.
- (Australia) A pie floater.
Derived terms 
See also 
a speck in the visual field that seems to move, possibly caused by degeneration of the vitreous humour