1.VerbTo 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
"water permeates sand"
2.VerbTo enter and spread through; to pervade.
"Bright sunshine permeates the room on a sunny day."
3.NounA watery by-product of milk production.
"(Can we add an example for this sense?)"
4.NounLiquid that has passed through a filtration system.