Supernatant

Part of speech: adjective (a.)

1. Swimming above; floating on the surface; as, oil supernatant on water. SUPERNATANT Su`per*na"tant, n. (Chem.)

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