sister

/ˈsɪs.tə(ɹ)/

//ˈsɪs.tə(ɹ)// noun

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

The verdict

“sister” is a regularly-used English word, ranked #1,207 in English word frequency and used as a noun.

#1,207
frequency rank, English
6
letters
9
tracked misspellings
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A daughter of the same parents as another person; a female sibling.

Visual similarity to commonly confused words

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

sister vs site
67% similar
sister vs sites
67% similar
sister vs system
67% similar

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

Key facts for sister
PropertyValue
Headwordsister
LanguageEnglish
Part of speechNoun
IPA/ˈsɪs.tə(ɹ)/
Letters6
Frequency rank#1,207
Misspellings tracked9
Confusable pairs20
SourceWiktionary (kaikki.org)

Where “sister” 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). sister 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 sister is 6 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈsɪs.tə(ɹ)/. Corpus data places it at rank #1,207 in overall English word frequency, indicating it appears regularly in written and spoken text. Wiktionary records 12 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 sister, with forms such as "isster", "sisetr", and "sisster". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 20 confusable-pair relationships, "site", "sites", "system", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.

Etymologically, the entry records: PIE word *swésōr From Middle English sister, suster, from Old English swustor, sweoster, sweostor (“sister, nun”); from Proto-Germanic *swestēr (“sister”), from Proto-Indo-European *swésōr (“sister”). Doublet of soror. Cognate with Scots sister, syster (“s… The correct English form is sister, spelled S-I-S-T-E-R.

Definition

  1. 1
    A daughter of the same parents as another person; a female sibling.
  2. 2
    A female member of a religious order; especially one devoted to more active service; (informal) a nun.
  3. 3
    Any butterfly in the genus Adelpha, so named for the resemblance of the dark-colored wings to the black habit traditionally worn by nuns.
  4. 4
    A senior or supervisory nurse, often in a hospital.
  5. 5
    Any woman or girl with whom a bond is felt through the same biological sex, gender or common membership in a community, race, profession, religion, organization, or ism.
  6. 6
    A black woman.
  7. 7
    A form of address to a woman.
  8. 8
    A female fellow member of a religious community, church, trades union etc.
  9. 9
    An entity that has a special or affectionate, non-hierarchical relationship with another.
  10. 10
    A node in a data structure that shares its parent with another node.
  11. 11
    Something in the same class.
  12. 12
    One of two tornados that form in close proximity at the same time or in quick succession.

Etymology

PIE word *swésōr From Middle English sister, suster, from Old English swustor, sweoster, sweostor (“sister, nun”); from Proto-Germanic *swestēr (“sister”), from Proto-Indo-European *swésōr (“sister”). Doublet of soror. Cognate with Scots sister, syster (“sister”), West Frisian sus, suster (“sister”), Dutch zuster (“sister”), German Schwester (“sister”), Norwegian Bokmål søster (“sister”), Norwegian Nynorsk and Swedish syster (“sister”), Icelandic systir (“sister”), Gothic 𐍃𐍅𐌹𐍃𐍄𐌰𐍂 (swistar, “sister”), Latin soror (“sister”), Russian сестра́ (sestrá, “sister”), Lithuanian sesuo (“sister”), Albanian vajzë (“girl, maiden”), Sanskrit स्वसृ (svásṛ, “sister”), Persian خواهر (xâhar, “sister”). In standard English, the form with i is due to contamination with Old Norse systir (“sister”). The plural sistren is from Middle English sistren, a variant plural of sister, suster (“sister”); compare brethren. The sense for "Adelpha-genus butterfly" is a semantic loan from translingual Adelpha, itself from Ancient Greek ἀδελφή (adelphḗ, “sister”).

This word in other languages

Common misspellings

Also misspelled as: isster,sisetr,sisster,sisterr,sistre,sistter,sitser,ssister,ssiter

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of sister - 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.

isster2sisetr2sisster1sisterr1sistre2sistter1sitser2ssister1
Edit distance from "sister"

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 "sister"?
"sister" is spelled S-I-S-T-E-R. The IPA pronunciation is /ˈsɪs.tə(ɹ)/.
What does "sister" mean?
As a noun, "sister" means: A daughter of the same parents as another person; a female sibling.
What words are commonly confused with "sister"?
"sister" is commonly confused with "site", "sites", "system". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "sister"?
The IPA (International Phonetic Alphabet) transcription for "sister" is /ˈsɪs.tə(ɹ)/. 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 "sister"?
PIE word *swésōr From Middle English sister, suster, from Old English swustor, sweoster, sweostor (“sister, nun”); from Proto-Germanic *swestēr (“sister”), from Proto-Indo-European *swésōr (“sister”). Doublet of soror. Cognate with Scots sister, ... 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 “sister”

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

  • The one correct English spelling is S-I-S-T-E-R - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈsɪs.tə(ɹ)/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “site” - see the side-by-side comparison. sister vs site
  • 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