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stepsister

American  
[step-sis-ter] / ˈstɛpˌsɪs tər /

noun

  1. one's stepfather's or stepmother's daughter by a previous marriage.

stepsister British  
/ ˈstɛpˌsɪstə /

noun

  1. a daughter of one's stepmother or stepfather by a union with someone other than one's father or mother respectively

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of stepsister

late Middle English word dating back to 1400–50; step-, sister

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

My stepsister and I are co-executors, but her past actions have caused me not to trust her.

From MarketWatch • Feb. 13, 2026

Hahn: It’s interesting, Mark, because I’ve always felt kind of like basically just invited to the party, so I always have felt like the messy stepsister on the outside looking in.

From Los Angeles Times • Jun. 5, 2025

I didn’t choose “Cinderella,” or the stepsister, the story of “Cinderella” through the stepsister chose me.

From Salon • Apr. 18, 2025

Baena's surviving family includes his mother Barbara Stern and stepfather Roger Stern; father Scott and stepmother Michele Baena; brother Brad Baena; stepsister Bianca Gabay and stepbrother Jed Fluxman.

From BBC • Jan. 7, 2025

Ash paused in the doorway, her back to her stepsister, and she wanted to tell her that she was not true; half her life was spent in secret.

From "Ash" by Malinda Lo

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.