FISSURE Meaning of FISSURE in English fis ‧ sure /ˈfɪʃə $ -ər/ BrE AmE noun [countable] [ Date: 1300-1400 ; Language: French ; Origin: Latin ; ⇨ ↑ fission ] a deep crack, especially in rock or earth Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012