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Synonyms

flatus

American  
[fley-tuhs] / ˈfleɪ təs /

noun

plural

flatuses
  1. intestinal gas produced by bacterial action on waste matter in the intestines and composed primarily of hydrogen sulfide and varying amounts of methane.


flatus British  
/ ˈfleɪtəs /

noun

  1. gas generated in the alimentary canal

"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 flatus

1660–70; < New Latin; Latin: a blowing, breathing, breath, equivalent to flā ( re ) to blow + -tus suffix of v. action

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.

Hydrogen is generated exclusively by microbes living in the gut, so continuously measuring hydrogen in flatus provides a direct signal of microbial fermentation activity as gut bacteria break down food components.

From Science Daily • Mar. 14, 2026

The extreme concentration of hydrogen in a flatus does make it easier to detect with a tiny sensor.

From The Wall Street Journal • Feb. 20, 2026

M Gove has promised to phase out diesel- and petrol-driven cars by 2040, a tiny flatus puff in a vast tornado, 22 years of slow death away.

From The Guardian • Jun. 3, 2018

Each day, up to 1500 mL of flatus is produced in the colon.

From Textbooks • Jun. 19, 2013

Stools: Piles; passes offensive flatus; stools soft and pappy; watery diarrhœa; stools hard, like stone, knotty.

From New, Old, and Forgotten Remedies: Papers by Many Writers by Anshutz, Edward Pollock