cycloelimination 

Synonym: cycloreversion
https://doi.org/10.1351/goldbook.C01501
The reverse of cycloaddition. The term is preferred to the synonyms 'cycloreversion', 'retro-addition' and 'retrocycloaddition'.
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1104 [Terms] [Paper]