Tra từ filter - Từ điển Oxford Advanced Learner 8th

fil·ter [filter filters filtered filtering] noun, verb BrE [ˈfɪltə(r)] NAmE [ˈfɪltər]
noun

1. 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.
2. a device that allows only particular types of light or sound to pass through it
•The camera has an anti-glare filter.
3. (computing)a program that stops certain types of electronic information, email, etc. being sent to a computer
4. (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
•a filter lane

Word Origin:
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.
Derived: ↑filter something out

verb
1. transitive ~ sth 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
2. transitive ~ sth to use a special program to check the content of emails or websites before they are sent to your computer
3. intransitive + adv./prep. (of people)to move slowly in a particular direction
•The doors opened and people started filtering through.
4. intransitive + adv./prep. (of information, news, etc.)to slowly become known
•More details about the crash are filtering through.
5. intransitive + adv./prep. (of light or sound)to come into a place slowly or in small amounts
•Sunlight filtered in through the curtains.
6. intransitive (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
Verb forms:

Word Origin:
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.

Thesaurus:
filter verb T
•All drinking water must be filtered.
strain • • purify • • sieve • • sift • • refine •
filter/strain/sieve/sift sth into sth
filter/strain/sieve sth through sth
filter/purify air/water

Example Bank:
•My secretary is very good at filtering my calls.
•The air was improving as the recyclers filtered out the smoke.
•Use a sunblock that filters UVA effectively.