Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “filter”

filter

noun [C] uk   /ˈfɪl.tər/ us    /-t̬ɚ/

filter noun [C] (EQUIPMENT)

C2 any of several types of equipment or devices for removing solids from liquids or gases, or for removing particular types of light: a water filter a dust filter I like to experiment with different light filters on my camera. Ozone is the Earth's primary filter for ultraviolet radiation.

filter noun [C] (TRAFFIC)

UK a green, arrow-shaped light that is part of a set of traffic lights and tells drivers when they can turn left or right: a traffic filter a left/right filter

filter

verb uk   /ˈfɪl.tər/ us    /-t̬ɚ/

filter verb (APPEAR GRADUALLY)

C2 [I + adv/prep] to appear or happen gradually or to a limited degree: News filtered down to us during the day. Reports about an accident began to filter in. Sunlight filtered through the branches.

filter verb (REMOVE)

C2 [T] to remove solids from liquids or gases, or to remove particular types of light, using special equipment: The water is filtered to remove any impurities. Devices in the two chimneys would filter (out) (= remove) radioactive dust.
Phrasal verbs
(Definition of filter from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of filter?
Browse related topics

You are looking at an entry to do with Separating and dividing, but you might be interested in these topics from the Cutting and joining topic area:

Add Cambridge dictionaries to your browser to your website

Definitions of “filter” in other dictionaries

Word of the Day

look on the bright side

to find good things in a bad situation

Word of the Day

The language of work

by Kate Woodford,
October 15, 2014
Most of us talk about our jobs. We tell our family and friends interesting or funny things that have happened in the workplace (=room where we do our job), we describe – and sometimes complain about – our bosses and colleagues and when we meet someone for the first time, we tell

Read More 

life tracking noun

October 20, 2014
the use of one or more devices or apps to monitor health, exercise, how time is spent, etc.

Read More