filter

/ˈfɪltə/

//ˈfɪltə// noun

By · According to Wiktionary data (CC BY-SA) ·

"filter" is a 6-letter English headword indexed on PlainSpell.

The verdict

“filter” is a regularly-used English word, ranked #4,449 in English word frequency and used as a noun.

#4,449
frequency rank, English
6
letters
9
tracked misspellings
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A device which separates a suspended, dissolved, or particulate matter from a fluid, solution, or other substance; any device that separates one substance from another.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

filter vs flyer
67% similar
filter vs filth
67% similar
filter vs finer
67% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for filter
PropertyValue
Headwordfilter
LanguageEnglish
Part of speechNoun
IPA/ˈfɪltə/
Letters6
Frequency rank#4,449
Misspellings tracked9
Confusable pairs20
SourceWiktionary (kaikki.org)

Where “filter” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). filter lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for filter is 6 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈfɪltə/. Corpus data places it at rank #4,449 in overall English word frequency, indicating it appears regularly in written and spoken text. Wiktionary records 7 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 9 likely wrong-spelling variants for filter, with forms such as "ffilter", "filetr", and "fillter". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 20 confusable-pair relationships, "flyer", "filth", "finer", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: From Middle English filtre, from Medieval Latin filtrum (compare also Old French feutre (“felt; filter”)), from Frankish *filtir, from Proto-West Germanic *felt. See felt. Doublet of phin. The correct English form is filter, spelled F-I-L-T-E-R.

Definition

  1. 1
    A device which separates a suspended, dissolved, or particulate matter from a fluid, solution, or other substance; any device that separates one substance from another.
  2. 2
    Electronics or software that separates unwanted signals (for example noise) from wanted signals or that attenuates selected frequencies.
  3. 3
    Any item, mechanism, device, or procedure that acts to separate or isolate.
  4. 4
    Self-restraint in speech.
  5. 5
    A non-empty upper set (of a partially ordered set) which is closed under binary infima (a.k.a. meets).
  6. 6
    A translucent object placed in the light path of a camera to remove certain wavelengths (colors), or a computer program that simulates such an effect.
  7. 7
    An appearance-altering digital image effect.

Etymology

From Middle English filtre, from Medieval Latin filtrum (compare also Old French feutre (“felt; filter”)), from Frankish *filtir, from Proto-West Germanic *felt. See felt. Doublet of phin.

Antonyms

ideal

This word in other languages

filtro(Español)filtre(Français)Filter(Deutsch)filtro(Português)

Common misspellings

Also misspelled as: ffilter,filetr,fillter,filterr,filtre,filtter,fitler,fliter,iflter

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of filter - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.

ffilter1filetr2fillter1filterr1filtre2filtter1fitler2fliter2
Edit distance from "filter"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "filter"?
"filter" is spelled F-I-L-T-E-R. The IPA pronunciation is /ˈfɪltə/.
What does "filter" mean?
As a noun, "filter" means: A device which separates a suspended, dissolved, or particulate matter from a fluid, solution, or other substance; any device that separates one substance from another.
What words are commonly confused with "filter"?
"filter" is commonly confused with "flyer", "filth", "finer". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "filter"?
The IPA (International Phonetic Alphabet) transcription for "filter" is /ˈfɪltə/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "filter"?
From Middle English filtre, from Medieval Latin filtrum (compare also Old French feutre (“felt; filter”)), from Frankish *filtir, from Proto-West Germanic *felt. See felt. Doublet of phin. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “filter”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is F-I-L-T-E-R - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈfɪltə/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “flyer” - see the side-by-side comparison. filter vs flyer
  • Browse more English words and confusable pairs in the same reference. English words
Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list