fissure

1 of 2

noun

fis·​sure ˈfi-shər 

1

: a narrow opening or crack of considerable length and depth usually occurring from some breaking or parting

a fissure in the earth's crust

2

a

: a natural cleft between body parts or in the substance of an organ

b

: a break or slit in tissue usually at the junction of skin and mucous membrane

3

: a separation or disagreement in thought or viewpoint : schism

fissures in a political party

fissure

2 of 2

verb

fissured; fissuring

transitive verb

: to break into fissures : cleave

intransitive verb

: crack, divide

Synonyms

Noun

• check
• chink
• cleft
• crack
• cranny
• crevice
• rift
• split

Examples of fissure in a Sentence

Noun

a fissure in the Earth's crust

a deep fissure in the ice

Recent Examples on the Web

Noun

But his return to center stage—or at least his self-invitation to it—is showing the fissures in a party that hasn’t fully decided if Biden is friend or foe, the party elder who stepped aside or the has-been who didn’t know when to exit. —Philip Elliott, Time, 8 May 2025

This case exposes a wide fissure in the foundation. —Melissa Quinn, CBS News, 2 May 2025

Verb

Although the year leading up to our wedding had altered our relationship, fissured it with cracks, the fundamental form remained — lovely in a different way, and more interesting. —Devon Fredericksen, New York Times, 17 Jan. 2025

One nasty cutback on his first touch fissured Buffalo’s defense for an 87-yard score. —Sam Cohn, Baltimore Sun, 27 Nov. 2024

Word History

Etymology

Noun

Middle English, borrowed from Middle French & Latin; Middle French fissure, borrowed from Latin fissūra "splitting, crack, opening," from fissus, past participle of findere "to split, cleave" + -ūra -ure — more at bite entry 1

Verb

derivative of fissure entry 1

First Known Use

Noun

14th century, in the meaning defined at sense 1

Verb

1656, in the meaning defined at transitive sense

Rhymes for fissure

• swisher
• wisher
• commissure
• kingfisher

Kids Definition

fissure

noun

fis·​sure

ˈfish-ər

1

: a narrow opening or crack

a fissure in rock

2

: a narrow natural space between body parts (as bones of the skull) or in the material making up an organ

fissure verb

Medical Definition

fissure

noun

fis·​sure ˈfish-ər, British also ˈfish-yu̇r 

1

: a natural cleft between body parts or in the substance of an organ: as

a

: any of several clefts separating the lobes of the liver

b

: any of various clefts between bones or parts of bones in the skull

c

: any of the deep clefts of the brain

especially : one of those located at points of elevation in the walls of the ventricles compare sulcus

d

: anterior median fissure

also : posterior median septum

2

: a break or slit in tissue usually at the junction of skin and mucous membrane

fissure of the lip

3

: a linear developmental imperfection in the enamel of a tooth

fissured

ˈfish-ərd, British also ˈfish-yu̇rd 

adjective