Meaning & use
filter
Last updated
Meanings
nouncountable
A device or layer of material that lets liquid or air pass but stops solid pieces or unwanted substances.
Grammar: Countable: a coffee filter, an air filter.
Patterns
- a filter for something
Replace the water filter every three months.
The coffee filter was full of grounds.
A cheap air filter can reduce dust at home.
nouncountablecomputing
A setting or program that selects only certain items from a larger set, such as in email or a search.
Grammar: Often in computing: a spam filter, a search filter.
Patterns
- a filter for something
My spam filter blocks most junk mail.
Use the price filter to see only cheaper hotels.
She added a filter to the photo to give it a warm glow.
verbtransitive
To pass a liquid or gas through a filter to remove unwanted material.
Grammar: Takes an object: filter the water.
Patterns
- filter something
- filter something out
Always filter the water before drinking from the stream.
He filtered the soup to remove the herbs.
The machine filters the air in the factory.
verbtransitive
To sort information or choices and keep only what you need.
Grammar: Often with out for removing, or by for sorting: filter out the noise.
Patterns
- filter something out
- filter something by something
You can filter the results by date.
The software filters out unwanted emails.
It takes practice to filter useful news from rumors.
verbintransitive
To move or spread slowly, little by little.
Grammar: No object; often with through, in, or into: sunlight filtered through the leaves.
Patterns
- filter through something
- filter into something
Sunlight filtered through the curtains.
News of the decision filtered out over the weekend.
Spectators began to filter into the stadium.
Word forms
| plural | filters |
|---|---|
| third person singular | filters |
| past tense | filtered |
| -ing form | filtering |
Common combinations
- water filter
- A water filter sits under the kitchen sink.
- spam filter
- The email was caught by the spam filter.
- filter out
- Headphones help filter out noise.
- apply a filter
- Apply a filter to narrow the search.
- filter through
- Light filtered through the leaves.
- coffee filter
- Put a fresh coffee filter in the machine.
Synonyms and how they differ
- strain
- Strain usually means pouring something through a sieve to separate solids, and is more hands-on and everyday than filter.
- sieve
- A sieve has a mesh for separating coarse parts from fine ones, while a filter can remove very small or invisible particles.
- screen
- Screen suggests checking people or things and rejecting some, as in screening calls, while filter suggests letting only part through.
- purify
- Purify means making something clean, and filtering is only one way to do it.
Word family
- filtration noun
- the process of passing something through a filter
- filtered adjective
- having been passed through a filter
- unfiltered adjective
- not passed through a filter or edited
- filtering noun
- the act of sorting or screening
- filterable adjective
- able to be filtered
Commonly confused: filter or philter? filter or sift?
filter vs philter
A philter, also spelled philtre, is a magic love potion, and it is pronounced the same but is unrelated to filtering.
filter vs sift
Sift means to separate fine parts from coarse parts of a dry material such as flour, while filter is mainly for liquids and gases.
Practice
Which phrase best completes: 'This app lets you ___ out messages from unknown senders.'
Choose one answer.
Filter out means to remove unwanted items from a larger set. Fill, fold and float do not take out here.
Make it your own
Write a sentence using “filter”, then check it and compare it with the examples above.