A long, narrow opening or line of breakage made by cracking or splitting, especially in rock or earth. The earthquake left a large fissure in the ground, making it difficult to cross the area safely.
A state of incompatibility or disagreement. The political party was weakened by a deep fissure between its progressive and conservative members.
A groove or natural division in an organ, such as the brain. The central fissure in the brain separates the frontal and parietal lobes.