\ 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

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 Kendall's little sis has also been known to rock her own collection of their iconic trucker hats on Instagram in the past. Zoë Weiner, Teen Vogue, "Kendall Jenner Wears a Von Dutch Trucker Hat to Drake's Birthday Party," 24 Oct. 2018 This isn't the 3-year-old princess' only protective big-sis moment from the christening, which took place last Monday. Emily Wang, Glamour, "Did You Catch This Cute Princess Charlotte Moment in Prince Louis' Christening Photo?," 16 July 2018 Last Fourth of July, big sis Khloé Kardashian posted a video to her Instagram stories, where Jenner and Simmons were in the background and getting cozy at a poolside get-together. Nicole Saunders, Harper's BAZAAR, "Kendall Jenner and Ben Simmons Flirt on Instagram and It's Not Subtle," 11 Jan. 2019

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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Dictionary Entries near sis







sisal rug

Statistics for sis

Last Updated

29 May 2019

Look-up Popularity

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).


showing courage and determination

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