[ floo ]
See synonyms for flu on Thesaurus.com
  1. a specific variety of influenza, usually named for its point of dissemination or its animal vector: Hong Kong flu; swine flu.

Origin of flu

First recorded in 1830–40; shortened form

Words that may be confused with flu

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use flu in a sentence

British Dictionary definitions for flu


/ (fluː) /

  1. the flu short for influenza

  2. any of various viral infections, esp a respiratory or intestinal infection

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

Scientific definitions for flu


[ flōō ]

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.