Cisdouble
Cisdouble is not a standard term in chemistry or related disciplines. In most contexts, it appears as a misspelling or shorthand for cis double bond, or for the cis/trans stereochemistry around a carbon–carbon double bond in alkenes. The cis configuration, also called Z in the CIP (Cahn–Ingold–Prelog) system, describes two substituents attached to the double‑bonded carbons that are on the same side of the bond. The opposite arrangement is trans (E).
Examples: cis-2-butene has two methyl substituents on the same side of the double bond; trans-2-butene has them
Beyond chemistry, "cisdouble" may appear as a coined term in software, datasets, or informal writing; its meaning
See also: cis–trans isomerism, E/Z nomenclature, alkenes, stereochemistry.