permeate UK /ˈpɜːmiˌeɪt/US /ˈpɝmiˌeɪ̯t/noun 2verb 2forms 3 noun2 •A watery by-product of milk production. •Liquid that has passed through a filtration system. verb2 •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 texturewater permeates sand •To enter and spread through; to pervade.Bright sunshine permeates the room on a sunny day. formspermeated · permeating · permeates