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 of musty

• stinking
• fusty
• ripe
• rotted
• stinky
• smelly
• rotting
• filthy
• fetid
• malodorous
• strong
• foul
• disgusting
• 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

Additionally, high moisture levels can cause a musty odor, experts say. —Emily Benda Gaylord, The Spruce, 23 Feb. 2026

Some of his customers swear by it for getting rid of stubborn pit stains and freshening up musty towels, too. —Melissa Locker, Southern Living, 22 Feb. 2026

Late summer or early fall is ideal because humidity levels are lower and carpets dry faster, helping prevent mildew and musty odors. —Mary Cornetta, Better Homes & Gardens, 21 Feb. 2026

There's an Unusual Odor A musty or earthy odor often means mold in the ducts, Goude warns, and a sharp, ammonia-like or animal odor is a sign of pests like rodents. —Rae Ford, Martha Stewart, 19 Feb. 2026

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