[ verb ] (chemistry) remove by passing through a filter
"filter out the impurities"
Used in print(Booth Hemingway and Stuart H. Brown,...)
Unless you want_to make your wife a pool widow and to spend a great many_of your leisure hours nursing your pool 's pristine purity , its care and feeding - from pH content to filtering and vacuuming - is best left to a weekly or bi-monthly professional service .
Once on the water , these little visitors seldom leave , and this adds to your filtering and vacuuming problems as_well as providing a slapping good time for all those present .
[ noun ] device that removes something from whatever passes through it
Used in print(A. N. Nagaraj and L. M. Black, "Localization of...)
The light_beam from the lamp was filtered through a half standard thickness Corning 1840 filter .
In the eyepiece a Wratten 2 B filter was used to filter off residual ultra-violet_light .(Ross E. McKinney and Howard Edde, "Aerated...)
Removal of the suspended solids by a membrane filter yielded an average effluent containing only 20 mg / l BOD .
[ noun ] (physics) n electrical device that alters the frequency spectrum of signals passing through it
Used in print(Walter H. Buchsbaum, "Advances in Medical Electronics"...)
Three different wavelengths of ultraviolet_radiation are selected by the variable filters placed in_front_of the three mercury xenon lights which serve as the ultraviolet sources .