filter
A device which separates a suspended, dissolved, or particulate matter from a fluid, solution, or other substance; any device that separates one substance from another.
Other meanings
Electronics or software that separates unwanted signals (for example noise) from wanted signals or that attenuates selected frequencies.
Any item, mechanism, device or procedure that acts to separate or isolate.
“He runs an email filter to catch the junk mail.”
Example sentences
Word history
From Medieval Latin "filtrum".
Where this comes from
This definition is adapted from “filter” on Wiktionary, by its contributors; example sentences are from Tatoeba, credited to their authors above, published under CC BY-SA 4.0. This page is published under the same licence.