musty

adjective

ˈmə-stē 

mustier; mustiest

1

a

: impaired by damp or mildew : moldy

old musty books

musty hay

b

: tasting of mold

musty wine

c

: smelling of damp and decay : fusty

The cellar was musty.

2

a

: trite, stale

musty prose

b(1)

: antiquated

musty customs

(2)

: superannuated

musty slang

mustily

ˈmə-stə-lē 

adverb

mustiness

ˈmə-stē-nəs 

noun

Synonyms

• stinking
• fusty
• ripe
• rotted
• stinky
• smelly
• rotting
• filthy
• fetid
• malodorous
• foul
• disgusting
• strong
• frowzy
• reeking
• funky
• frowsy
• dirty
• rotten
• noisome

Choose the Right Synonym for musty

malodorous, stinking, fetid, noisome, putrid, rank, fusty, musty mean bad-smelling.

malodorous may range from the unpleasant to the strongly offensive.

malodorous fertilizers

stinking and fetid suggest the foul or disgusting.

prisoners were held in stinking cells

the fetid odor of skunk cabbage

noisome adds a suggestion of being harmful or unwholesome as well as offensive.

a stagnant, noisome sewer

putrid implies particularly the sickening odor of decaying organic matter.

the putrid smell of rotting fish

rank suggests a strong unpleasant smell.

rank cigar smoke

fusty and musty suggest lack of fresh air and sunlight, fusty also implying prolonged uncleanliness, musty stressing the effects of dampness, mildew, or age.

a fusty attic

the musty odor of a damp cellar

Examples of musty in a Sentence

a dark and musty basement

the musty prose of writers who use the same expressions over and over

Recent Examples on the Web

First up, avoid musty smells by moving towels to the dryer as soon as the wash cycle is complete. —Patricia Shannon, Southern Living, 6 July 2025

On July 12, after days of continuous rain, a musty heat spread across the Chicago region and temperatures soared with a record-high heat index of about 126 degrees. —Adriana Pérez, Chicago Tribune, 6 July 2025

In water, these compounds are responsible for the musty, moldy taste that indicates that water isn’t safe to drink. —Tom Hawking, Popular Science, 12 June 2025

Signs that a sauna needs to be cleaned include foul or musty odors, visible dirt, and/or the appearance of mold or mildew. —Jolie Kerr, Better Homes & Gardens, 20 May 2025

Word History

Etymology

must entry 4

First Known Use

1530, in the meaning defined at sense 1a

Rhymes for musty

• crusty
• dusty
• gusty
• lusty
• rusty
• trusty

Kids Definition

musty

adjective

ˈməs-tē 

mustier; mustiest

1

a

: affected by dampness or mildew : moldy

b

: tasting or smelling of dampness and decay

2

a

: stale entry 1 sense 2, trite

musty proverbs

b

: outmoded, antiquated

musty traditions

mustiness noun