isomer

[ ahy-suh-mer ]

noun

1. Chemistry. a compound displaying isomerism with one or more other compounds.
2. Also called nuclear isomer. Physics. a nuclide that exhibits isomerism with one or more other nuclides.

isomer

/ ˌaɪsəˈmɛrɪk; ˈaɪsəmə /

noun

1. chem a compound that exhibits isomerism with one or more other compounds
2. physics a nuclide that exhibits isomerism with one or more other nuclides

isomer

/ ī′sə-mər /

1. Chemistry.
   Any of two or more substances that have the same molecular formula but differ in their connectivity or spatial arrangement of atoms, or in their topology in macromolecules.
2. Physics.
   Any of two or more nuclei with the same mass number and atomic number that have different radioactive properties and can exist in any of several energy states for a measurable period of time.

Derived Forms

• isomeric, adjective

Word History and Origins

Origin of isomer¹

First recorded in 1865–70; back formation from isomeric

Example Sentences

In the new analysis, the researchers measured more than a dozen other life-related compounds, including isomers of the nucleobases, Glavin says.

From Science News

If there had been contamination from the soil, we should have seen those isomers in the soil as well.

From Science News

The law creates a new class of “adult-use cannabis” products for anything that contains THC, its isomers, or “any artificially derived cannabinoid that is reasonably determined to have an intoxicating effect.”

From FiveThirtyEight

Congress appeared to legalize all of these other compounds by including “all derivatives, extracts, cannabinoids, isomers, acids, salts, and salts of isomers” in their definition of hemp.

From FiveThirtyEight

Sometimes either form was digestible, but frequently the body could use only the isomer to which it was adjusted.

From Project Gutenberg

According to this view hyoscyamine ought to be the hyoscinate of hyoscine, or at any rate an isomer of this body.

From Project Gutenberg

An isomer of chloral, parachloralide, is made by passing excess of dry chlorine into absolute methyl alcohol.

From Project Gutenberg

Besides this oil, cloves also contain two neutral bodies, eugenin and caryophyllin, the latter of which is an isomer of camphor.

From Project Gutenberg

Chavibetol, an isomer of eugenol, occurs in the ethereal oil obtained from Piper betle.

From Project Gutenberg