\ ˈsis How to pronounce sis (audio) \

Definition of sis

 (Entry 1 of 3)

: sister usually used in direct address

Definition of SIS (Entry 2 of 3)

Secret Intelligence Service

Note: The Secret Intelligence Service is a British government agency that is responsible for the collection and analysis of information about foreign countries or groups.

plural -ses

Definition of -sis (Entry 3 of 3)

: process : action peristalsis

Examples of sis in a Sentence

Recent Examples on the Web: Noun

The dinosaur that made them was a theropod, probably Coelophysis (see-low-FY-sis), a meat-eater that stood about 7 feet tall. David Lyon,, "Making tracks: Walking in the footsteps of New England dinosaurs," 18 June 2019 Her home life can feel sketchy, despite the cheerful presence of Storm Reid as her little sis. Darren Franich,, "HBO's teen shock-soap Euphoria is sweeter than you think: EW review," 14 June 2019 Jenner also made some time in her busy schedule to catch up with her supermodel big sis, Kendall. Megan Decker, Harper's BAZAAR, "Kylie Jenner and Travis Scott Made a Stylish Appearance in NYC Without Baby Stormi," 7 May 2018 But now, his big sis gets to remain as number four. Blake Bakkila, Good Housekeeping, "How Royal Baby Archie Changes the Succession of the British Throne," 8 May 2019 The youngest Jenner teamed up with her big sis Kendall for yet another epic fashion collab. Kelsey Stiegman, Seventeen, "Kendall and Kylie Jenner Dropped an EPIC New Handbag Line at Walmart – And It's All Under $40," 2 Nov. 2018 Solange danced with her big sis on stage and loved every minute of it. Hilary Hughes, Billboard, "Coachella 2018: How Rihanna, Lauren Jauregui & More VIPs Spent Weekend 1," 14 Apr. 2018 Keep calm and enjoy the birthday, sis Thanks for continuing the tradition of getting older with me. Vara Gianna, Seventeen, "46 Instagram Captions for Sisters That Are Perfect for Your Next Fire Pic," 20 Mar. 2019 Although the role isn't common for British weddings (Meghan Markle, for example, didn't have one), Eugenie made an exception for her big sis. Erica Gonzales, Harper's BAZAAR, "Princess Beatrice Was a Royal Unicorn for Halloween," 1 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sis


1596, in the meaning defined above

History and Etymology for sis

Noun suffix

Latin, from Greek, feminine suffix of action

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Statistics for sis

Last Updated

26 Jun 2019

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Time Traveler for sis

The first known use of sis was in 1596

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More from Merriam-Webster on sis

Rhyming Dictionary: Words that rhyme with sis

Comments on sis

What made you want to look up sis? Please tell us where you read or heard it (including the quote, if possible).


to take the place or position of

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