sister-in-law
Pluralsisters-in-law
- 1The sister of one's husband or wife.
When I married, my husband's sister welcomed me warmly, and we have been close as sister-in-law and brother's wife ever since.
She invited her sister-in-law, her wife's older sister, to spend the holidays with them.
Oppositebrother-in-law
Note
The compound is older than it looks: Middle English already said suster-in-lawe, built from sister and -in-law. The plural attaches to the first element, giving sisters-in-law, because sister is the noun doing the work. Sister-in-laws turns up in casual speech but is nonstandard, so keep it out of careful writing.
- 2The wife of one's brother or sister.
My sister-in-law and my brother just bought their first house together.
After my sister's wedding, her new wife quickly became the sister-in-law I see most often.
Oppositebrother-in-law
Note
Here the marriage that creates the tie is your sibling's, not your own. Together with the spouse's sister, it forms the everyday core of the word: a woman of your own generation, one marriage away from you. When it matters which one you mean, the plain phrases "my brother's wife" and "my wife's sister" make the difference clear.
- 3A woman married to a brother or sister of one's husband or wife.
Both of us married into the same family, so my sister-in-law and I share the same in-laws without being related by blood.
When my wife's brother wed, his new wife became the sister-in-law who hosts our reunions.
Oppositebrother-in-law
Note
A relationship two marriages deep: the two of you are connected only because each of you married into the same family. Its more exact name is co-sister-in-law, a term that also covers the sister of a sibling's spouse. Calling her simply a sister-in-law is uncommon and can confuse listeners, so "my husband's brother's wife" is the safer choice when precision counts.
Less common meaning
- 4The sister of one's sibling's spouse.
My brother's wife brought along her sister, who has been a friendly sister-in-law to me ever since.
Once my sister married, I gained a sister-in-law in the form of her husband's sister.
Oppositebrother-in-law
Use it in a sentence
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Origin
Inherited from Middle English suster-in-lawe, formed from "sister" combined with the suffix "-in-law".