Metamerism
Metamerism , noun
1.
(Biology) The symmetry of a metameric structure; serial symmetry; the state of being made up of metameres.
2.
(Chemistry) The state or quality of being metameric; isomerism due to different bonding patterns in two substances having the same molecular formula. Contrasted with steroisomerism or optical isomerism. Also, the relation or condition of metameric compounds.