hypotonic

adjective

hy·​po·​ton·​ic ˌhī-pə-ˈtä-nik How to pronounce hypotonic (audio)
-pō-
1
: having deficient tone or tension
hypotonic children
2
: having a lower osmotic pressure than a surrounding medium or a fluid under comparison
hypotonic organisms
hypotonicity
ˌhī-pə-tə-ˈni-sə-tē How to pronounce hypotonic (audio)
-pō-
noun

Examples of hypotonic in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
On the contrary, a hypotonic pelvic floor is when the muscles are flaccid and not very reactive. — Mónica Heras, Vogue, 20 Aug. 2025 Less than two months after The Lancet publication, Latta performed the first therapeutic intravenous resuscitation in May of 1832 with infusions of a homemade solution, a watery hypotonic mix of sodium, chloride, and bicarbonate. — Rebecca Kreston, Discover Magazine, 31 May 2016 On Tuesday, the Real Housewives of Orange County alum, 36, recounted a heartbreaking story on Instagram involving her 3-year-old son Hart, who was diagnosed with hypotonic cerebral palsy last October. — Georgia Slater, PEOPLE.com, 8 Sep. 2021

Word History

Etymology

International Scientific Vocabulary

First Known Use

1895, in the meaning defined at sense 1

Time Traveler
The first known use of hypotonic was in 1895

Rhymes for hypotonic

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Browse Nearby Words

hypotonia
hypotonic
hypotrachelium
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Cite this Entry

“Hypotonic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hypotonic. Accessed 7 Jul. 2026.

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Medical Definition

hypotonic

adjective
hy·​po·​ton·​ic ˌhī-pə-ˈtän-ik, -pō- How to pronounce hypotonic (audio)
1
: having deficient tone or tension
hypotonic children
2
: having a lower osmotic pressure than a surrounding medium or a fluid under comparison
a hypotonic solution
compare hypertonic sense 2, isotonic sense 1
hypotonically
-i-k(ə-)lē How to pronounce hypotonic (audio)
adverb
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