alkenes

https://doi.org/10.1351/goldbook.A00224
Acyclic branched or unbranched hydrocarbons having one carbon–carbon double bond and the general formula CnH2n. Acyclic branched or unbranched hydrocarbons having more than one double bond are alkadienes, alkatrienes, etc.
See also: olefins
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1313 (https://doi.org/10.1351/pac199567081307)