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Synonyms

sis

1 American  
[sis] / sɪs /

noun

Informal.

  1. sister.

-sis 2 American  

  1. a suffix appearing in loanwords from Greek, where it was used to form from verbs abstract nouns of action, process, state, condition, etc..

    thesis; aphesis.
SIS 1 British  

abbreviation

  1. Also called: MI6.  (in Britain) Secret Intelligence Service

  2. (in New Zealand) Security Intelligence Service

"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
sis 2 British  
/ sɪs /

noun

  1. informal short for sister

"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
sis 3 British  
/ siːs, sɪs /

interjection

  1. informal an exclamation of disgust

"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 sis1

1825–35, shortened form; compare Dutch zus for zuster sister

Origin of -sis2

From Greek

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.

You’ve said your sis won’t stop harping on your solution, which suggests there’s a deeper issue here.

From Slate • Mar. 20, 2024

But your sis and brother-in-law didn’t “hurt” him in the sense of showing malice or intending harm.

From Washington Post • Feb. 28, 2023

Dee and Lee’s youngest boy sleeping in their bedroom till he’s 5 or 6, then sharing a room with his big sis.

From New York Times • Dec. 27, 2022

"Hey sis sorry I haven't been much on communication recently. This time of year is always rough," he wrote.

From Salon • Nov. 11, 2022

“Your mom and sis have skills,” Kiki says, rolling the key chain around in one hand while pushing the stroller back and forth.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith

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.