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Synonyms

musty

1 American  
[muhs-tee] / ˈmʌs ti /

adjective

mustier, mustiest

  1. having an odor or flavor suggestive of mold, as old buildings, long-closed rooms, or stale food.

    Synonyms:
    stale, moldy, dank

  2. obsolete; outdated; antiquated.

    musty laws.

  3. dull; apathetic.

musty 2 American  
[muhs-tee] / ˈmʌs ti /

noun

plural

musties

  1. (formerly) a kind of snuff having a musty flavor.

musty British  
/ ˈmʌstɪ /

adjective

  1. smelling or tasting old, stale, or mouldy

  2. old-fashioned, dull, or hackneyed

    musty ideas
"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

  • mustily adverb
  • mustiness noun

Etymology

Origin of musty1

1520–30; perhaps variant of moisty ( Middle English; moist, -y 1 ) with loss of i before s as in master

Origin of musty2

First recorded in 1700–10; noun use of musty 1

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.

New research now shows that the distinctive musty scent of mummified remains holds valuable clues about how these elaborate burial rituals were carried out.

From Science Daily • Mar. 16, 2026

Notwithstanding some clunky moments, Mr. Ansari not only engineers up-to-the-minute twists on the musty Hollywood angel movie, but decorates his story with clever dialogue and wicked observations about street-level existence in the City of Angels.

From The Wall Street Journal • Oct. 16, 2025

It was musty and slightly astringent, not unlike the communal bin area in his block of flats.

From BBC • Sep. 25, 2025

Although the troubles of our world never bled into “What We Do in the Shadows,” the story never shied away from politics within its own musty, rotten realm.

From Salon • Nov. 11, 2024

The apartment smells musty, but it looks tidy.

From "Dragons in a Bag" by Zetta Elliott

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.