\ 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 Though most associate the cosmic event with utter chaos in the personal lives (please don’t text your ex back, sis!), for others, the retrograde is a chance to usher in a new beginning. Ineye Komonibo,, "Rihanna Is Reportedly Single (And Still Withholding Her Album)," 19 Jan. 2020 Just in case some of us forgot: transphobia ain't cute, sis. Kori Williams, Seventeen, "Too Faced Co-Founder Fires His Sister Over Transphobic Comments About NikkieTutorials," 15 Jan. 2020 At their wedding, Knowles and Ferguson both wore ivory, a color also worn by key attendees, including the bride's mother Tina, brother-in-law Jay Z, niece Blue Ivy and big sis Beyonce. Charles Trepany, USA TODAY, "Solange Knowles announces split from husband Alan Ferguson, talks 'spiritual transition'," 2 Nov. 2019 My sis is trying to update the condo and make sure my brother moves out as soon as Mom passes. Carolyn Hax, oregonlive, "Carolyn Hax: Siblings squabble over elderly mother’s care/living situation," 22 Oct. 2019 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

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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Last Updated

20 Feb 2020

Cite this Entry

“Sis.” Dictionary, Merriam-Webster, Accessed 29 Feb. 2020.

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Rhyming Dictionary: Words that rhyme with sis

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