diastereoisomerism

noun

dia·​stereoisomerism ¦dīə+ How to pronounce diastereoisomerism (audio)
plural -s
: optical isomerism of compounds whose molecules contain more than one asymmetric atom and do not exhibit mirror-image relationship (such as glucose and galactose or meso-tartaric acid and dextro-tartaric acid)
distinguished from enantiomorphism
compare asymmetric carbon atom

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“Diastereoisomerism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diastereoisomerism. Accessed 26 Dec. 2025.

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