from Wiktionary, Creative Commons Attribution/Share-Alike License
- Designating an achiral member of a group of diastereoisomers that has at least one chiral member
from the GNU version of the Collaborative International Dictionary of English
- A combining form denoting in the middle, intermediate.
- Denoting a type of hydrocarbons which are regarded as methenyl derivatives. Also used adjectively.
- Optically inactive due to compensating optical activity at two or more asymmetric centers, often due to a plane of symmetry within the molecular structure.
- Attached to a carbon atom located between two hereoatoms in a heterocyclic ring.
from The Century Dictionary and Cyclopedia
- A combining form used in organic chemistry to indicate optical inactivity through internal compensation. See mesoform.
From Ancient Greek μέσος (mésos, "middle"). (Wiktionary)