- cis-trans isomerism
- /ˌsɪs-trænz aɪˈsɒmərɪzəm/ (say .sis-tranz uy'somuhrizuhm)
a form of isomerism occurring in a molecule which is rigid because it contains a double bond or ring system. The cis-isomer has specific groups on the same side, and the trans-isomer on the opposite sides of the molecule.
Australian English dictionary. 2014.