What is the meaning of fissure in English?

Learn vocabulary with pictures as well as definitions of fissure in English

Prolonged indent, located in certain organs of the body, such as between the brain's hemispheres.

Elongated opening in the ground or a solid body.

Prolonged cleft located on the pulmonary surface, which separates the lobes.

Prolonged cleft located on the pulmonary surface, which separates the lobes.