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Synonyms

fatty

1 American  
[fat-ee] / ˈfæt i /

adjective

fattier, fattiest

  1. consisting of, containing, or resembling fat.

    fatty tissue.

  2. Pathology. characterized by overproduction or excessive accumulation of fat.

fatty 2 American  
[fat-ee] / ˈfæt i /

noun

Informal.

plural

fatties

  1. Disparaging and Offensive. a person who is overweight or obese (sometimes used as a term of address).

  2. a large marijuana cigarette, often shared and consumed by a group, with a shape and size similar to a cigar.

fatty British  
/ ˈfætɪ /

adjective

  1. containing, consisting of, or derived from fat

  2. having the properties of fat; greasy; oily

  3. (esp of tissues, organs, etc) characterized by the excessive accumulation of fat

"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

noun

  1. informal a fat person

"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

Other Word Forms

Etymology

Origin of fatty1

Middle English word dating back to 1350–1400; see origin at fat, -y 1

Origin of fatty2

First recorded in 1790–1800 fatty 2 ( def. 1 ); 2003 fatty 2 ( def. 2 ); see origin at fat, -y 2

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.

And gone was the owner of the irreverent nickname "Fatty Lai": he had lost considerable weight.

From BBC • Dec. 20, 2025

The Fatty Bistro Salad is one that I find everyone, including my own picky 6 year old, finds hard to turn down.

From Salon • May 2, 2024

"Fatty liver can result in complications like liver cirrhosis and liver failure. This study helps us understand more about the biology underlying these diseases in humans."

From Science Daily • Mar. 18, 2024

Every chance they get, they go back to Killer Burger and load up on Fatty Benders.

From Los Angeles Times • Sep. 6, 2023

In ball I was helped briefly by a thin black man called Fatty who was the coach of a team called the Comanches, one of the best teams in the city.

From "Bad Boy" by Walter Dean Myers

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.