: a hydrate (such as plaster of paris) containing half a mole of water to one mole of the compound forming the hydrate

Word History

First Known Use

circa 1901, in the meaning defined above

Time Traveler
The first known use of hemihydrate was circa 1901

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Cite this Entry

“Hemihydrate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hemihydrate. Accessed 28 Mar. 2025.

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