- A long narrow opening; a crack or cleft.
- The process of splitting or separating; division.
- A separation into subgroups or factions; a schism.
- Anatomy A normal groove or furrow, as in the liver or brain, that divides an organ into lobes or parts.
- Medicine A break in the skin, usually where it joins a mucous membrane, producing a cracklike sore or ulcer.
intr. & tr.v.fis·sured, fis·sur·ing, fis·sures
Origin of fissureMiddle English cut from Old French from Latin fissūra from fissus split ; see fissi- .