stereoisomer

1 of 2

noun (1)

: any of a group of isomers in which atoms are linked in the same order but differ in their spatial arrangement

stereoisomerism

2 of 2

noun (2)

: isomerism in which atoms are linked in the same order but differ in their arrangement in space
sometimes distinguished from structural isomerism
see geometric isomerism, optical isomerism

Word History

Etymology

Noun (1)

International Scientific Vocabulary

Noun (2)

stere- + isomerism

First Known Use

Noun (1)

1894, in the meaning defined above

Time Traveler
The first known use of stereoisomer was in 1894

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Cite this Entry

“Stereoisomer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/stereoisomer. Accessed 8 Jul. 2026.

Medical Definition

: any of a group of isomers in which atoms are linked in the same order but differ in their spatial arrangement
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