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

Over time, these filters can clog with buttons, bobby pins, small bits of fuzz, and more, leading to more serious issues like musty odors and drainage problems. — Kate Van Pelt, The Spruce, 17 Aug. 2026

Damp basement walls, musty odors, and water stains around basement windows are all signs that water may be entering your home’s foundation. — Olivia McIntosh, Martha Stewart, 3 Aug. 2026

Try to clean your front load washing machine every 30 days to keep it from ever getting to the smelly, musty stage. — Daley Quinn, Southern Living, 3 Aug. 2026

Likewise, burning smells, musty odors, unexpected water around the indoor unit or ice forming on refrigerant lines can all signal that another issue remains or that the repair wasn't completed correctly. — Angelica Leicht, CBS News, 31 July 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