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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.

“We’ve got you, sis,” Ms. Pressley tweeted, along with a photo of her holding a sign that reads “housing is a human right.”

From Washington Times

Start with the power-of-attorney sis and work outward from there, as appropriate.

From Washington Post

"Omg sis. You do look so much younger cause I'm 54 and you are my new favorite TikToker," one woman wrote.

From Fox News

“Three seasons carrying a drama series on her slender yet mighty shoulders. Bask, sis. BAAAAASK.”

From Los Angeles Times

“Another update, lettuce has crack because your sis is gone,” she adds again, looking like she’s on the verge of falling asleep.

From New York Times