Isomere
/ˈaɪ.sə.mɪər/noun
An obsolete or variant form of isomer, a compound having the same molecular formula as another compound but a different arrangement of atoms.
Did you know?Isomery shows that identical ingredients do not guarantee identical effects: molecular arrangement can transform a substance’s properties, sometimes dramatically.
Etymological Timeline
Proto-Indo-European
PIE
*sem-
“One; together or unified—an ancient root associated with sameness.”
Ancient Greek
Greek
isos
“Equal or like.”
Ancient Greek
Greek
meros
“Part or portion.”
19th Century
French
isomère
“A chemical compound composed of the same elements in the same proportions as another, but differing in structure.”
19th Century
English
isomere
“An obsolete or variant English form of isomer.”
Modern English
English
isomer
“A compound with the same molecular formula as another compound but a different molecular structure.”
Explore more surprising origins