supernatant

adj. floating above or on the surface

Supernatant is the adjective for any liquid above non-soluble solids/precipitates and it means floating above (see http://www.answers.com/supernatant). Supernate (noun) refers to the actual liquid or the clear fluid above a sediment or precipitate. The solids may reach the bottom of a container by means of settling, sedimentation, precipitation, or centrifugation. Use of supernatant in scientific papers referring to supernate has been a common engraved mistake.
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Supernatant /su·per·na·tant/ the liquid lying above a layer of precipitated insoluble material. supernatant the liquid lying above a layer of [more]Supernatant - Community and Resources

Noun
1. a liquid lying above a sediment (floating on the surface)
(hypernym) liquid
Adjective
1. of a liquid; floating on the surface above a sediment or precipitate; "the supernatant fat was skimmed off"
(similar) supported
(classification) chemistry, chemical science

(n.)
The liquid remaining after solids suspended in the liquid have been sedimented by gravity or by centrifugation. Contrasted with the solid sediment, or (in centrifugation) the pellet.
  

(a.)
Swimming above; floating on the surface; as, oil supernatant on water.