\ 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

Researchers from around the Gulf and in New York have named the species the American pocket shark, or Mollisquama (mah-lihs-KWAH-muh) mississippiensis (MISS-ih-sip-ee-EHN-sis). Janet Mcconnaughey,, "Pocket-sized shark squirts glowing clouds from pockets," 20 July 2019 Particularly fun, with a side of naughty, is a night out with her soon-to-be-wed sis at a bar inspired by Josephine Street. Jeanne Jakle,, "The 15 new fall 2019 TV shows you need to watch," 12 Sep. 2019 With Billy Porter and MJ Rodriguez. 10 p.m. FX Rah, rah, sis-boom-bah! Matt Cooper,, "What’s on TV, June 9-15: ‘Jessica Jones,’ ‘Big Little Lies,’ a Doris Day tribute and more," 7 June 2019 With the help of little sis, Karin, Vonn and Suban hit it off — although Vonn was still dating someone else at the time. The Denver Post, "Lindsey Vonn and NHL star P.K. Subban announce engagement," 23 Aug. 2019 Now, all Max needs is a step brother and a maniacal little sis! Carolyn Twersky, Seventeen, "Josh Peck Just Became a Dad!," 2 Jan. 2019 Our President sis on schedule to forge a relationship with North Korea in Singapore that will cause Pyongyang to dismantle its nuclear weapons. Fox News, "Trump slams 'meek' Trudeau for 'dishonest' news conference," 10 June 2018 Their mini reunion comes months after Jordyn was accused of hooking up with Tristan Thompson, then-boyfriend of Kylie’s big sis Khloé Kardashian (and father to Khloé’s child, True Thompson). Teen Vogue, "Jordyn Woods and Kylie Jenner Reunited at a Club Party in Hollywood, Months After Tristan Thompson Rumors," 11 June 2019 My sis is trying to update the condo and make sure my brother moves out as soon as my Mom passes. The Washington Post, "Carolyn Hax Live: 'The cat is your guardian angel'," 25 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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Statistics for sis

Last Updated

2 Oct 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).


involving a confidence or trust

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