Meaning of FILTER in English

/ ˈfɪltə(r); NAmE / noun , verb

■ noun


a device containing paper, sand, chemicals, etc. that a liquid or gas is passed through in order to remove any materials that are not wanted :

an air / oil filter

a coffee / water filter

filter paper for the coffee machine

He smokes cigarettes without filters.

—picture at cafetiere , laboratory


a device that allows only particular types of light or sound to pass through it


( computing ) a program that stops certain types of electronic information, email, etc. being sent to a computer


( BrE ) a light on a set of traffic lights showing that traffic can turn left or right while traffic that wants to go straight ahead must wait

■ verb


[ vn ] to pass liquid, light, etc. through a special device, especially to remove sth that is not wanted :

All drinking water must be filtered.

Use a sun block that filters UVA effectively.

( figurative )

My secretary is very good at filtering my calls (= making sure that calls that I do not want do not get through) .

—see also filtration


[ vn ] to use a special program to check the content of emails or websites before they are sent to your computer


[ v + adv. / prep. ] ( of people ) to move slowly in a particular direction :

The doors opened and people started filtering through.


[ v + adv. / prep. ] ( of information, news, etc. ) to slowly become known :

More details about the crash are filtering through.


[ v + adv. / prep. ] ( of light or sound ) to come into a place slowly or in small amounts :

Sunlight filtered in through the curtains.


[ v ] ( BrE ) ( of traffic at traffic lights ) to turn left at traffic lights while other vehicles wanting to go straight ahead or turn right must wait


- filter sth out



late Middle English (denoting a piece of felt): from French filtre , from medieval Latin filtrum felt used as a filter, of West Germanic origin and related to felt .

Oxford Advanced Learner's English Dictionary.      Оксфордский английский словарь для изучающик язык на продвинутом уровне.