FILTER

[verb] [T], [noun] [C] - (to use or act as) any of several types of equipment or devices for removing solids from liquids or gases, or for removing particular types of light, or (figurative) a way of removing part of somethingan oil/water filtera dust filterI like to experiment with different light filters on my camera.Ozone is the earth's primary filter for ultraviolet radiation.(figurative) The interviewers would act as a filter and see that urgent cases received attention first. [C]A filter bed is an area of stones and sand through which water flows to be cleaned.(UK) A traffic filter (US and ANZ right/left turn lane) is one row of traffic, controlled by a green arrow-shaped light, which turns left or right while other rows do not move.a left/right filter [C]You'll have to get into the left filter at the lights. [C]Filter left (= move in this row of traffic). [I usually + adverb or preposition]Mussels filter 50 litres of water daily to extract food. [T]Devices in the two chimneys would filter (out) radioactive dust from smoke released into the air. [T]To filter down, in, out and through means 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.Word began to filter out about the changes.Payments have started to filter through to the office.Sunlight filtered through the branches.When driving, to filter in (US merge) is to join a line of moving traffic without causing other vehicles to slow down.(UK) Filter coffee is made by hot water flowing slowly through crushed coffee beans in a coffee filter.A filter paper is a paper cone which allows only liquid to flow through, and is used to make filter coffee.A filter tip/filter-tipped cigarette is a cigarette with a filter on the end to remove tar from the tobacco.