sister-in-law
/ˈsɪs.tɚ.ɪn.lɔ/
"sister-in-law" is a 11-letter English headword indexed on PlainSpell.
The verdict
“sister-in-law” is outside the top-ranked English vocabulary, used as a noun - the kind of word writers most often double-check.
- Unranked
- below top-frequency English
- 13
- letters
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A female relative of one's generation, separated by one degree of marriage:
| Property | Value |
|---|---|
| Headword | sister-in-law |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈsɪs.tɚ.ɪn.lɔ/ |
| Letters | 13 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “sister-in-law” sits in English frequency
Spelling & Dictionary Insight
The English entry for sister-in-law is 13 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈsɪs.tɚ.ɪn.lɔ/. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader. Wiktionary records 4 distinct senses for this headword, so context determines which meaning a reader should apply.
sister-in-law has no tracked misspelling variants, suggesting the orthography follows predictable English patterns. No confusable counterpart is on file for this word, since nothing in our dataset looks or sounds close enough to cause mix-ups.
Etymologically, the entry records: Inherited from Middle English suster-in-lawe; equivalent to sister + -in-law. The correct English form is sister-in-law, spelled S-I-S-T-E-R---I-N---L-A-W.
Definition
- 1A female relative of one's generation, separated by one degree of marriage:
- 2A female relative of one's generation, separated by one degree of marriage:
- 3Co-sister-in-law: The wife of one's sibling-in-law.
- 4Co-sister-in-law: The wife of one's sibling-in-law.
Etymology
Inherited from Middle English suster-in-lawe; equivalent to sister + -in-law.
This word in other languages
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
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Using “sister-in-law”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is S-I-S-T-E-R---I-N---L-A-W - every other letter order is a misspelling in standard orthography.
- Say it as /ˈsɪs.tɚ.ɪn.lɔ/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- 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.