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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)
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