Definition of fissure
a long, narrow opening or line of breakage made by cracking or splitting, especially in rock or earth.
chiefly Anatomy a long narrow opening in the form of a crack or groove, e.g., any of the spaces separating convolutions of the brain.
a state of incompatibility or disagreement:the fissure between private sector business and the newly expanding public sector
verb [with object] (usually as adjective fissured)
split or crack (something) to form a long narrow opening:the skin becomes dry, fissured, and cracked