Definition of chiral in US English:



  • Asymmetric in such a way that the structure and its mirror image are not superimposable. Chiral compounds are typically optically active; large organic molecules often have one or more chiral centers where four different groups are attached to a carbon atom.

    • ‘The second type is the cholesteric liquid crystal phase, also called the chiral nematic liquid crystal phase.’
    • ‘A molecule that is not symmetric - that is, a molecule without a plane of symmetry - is termed dissymmetric, or chiral.’
    • ‘The resulting chiral nematic giant liquid crystals had wide temperature ranges for their liquid crystal phases, from room temperature to about 80° Celsius.’
    • ‘The most common examples of chiral molecules are enantiomers.’
    • ‘Most alkaloids are also chiral molecules, meaning they have nonsuperimposable mirror images.’


Late 19th century: from Greek kheir ‘hand’ + -al.