Foam formed by water and a fluorocarbon surfactant, used in firefighting because it floats on flammable liquids lighter than water.
Water in its standard form of H₂O, containing two protium hydrogen atoms, as opposed to heavy water.
Liquid that has passed through a filtration system.
A watery by-product of milk production.
To pass through the pores or interstices of; to penetrate and pass through without causing rupture or displacement; applied especially to fluids which pass through substances of loose texture
To enter and spread through; to pervade.