molecular weight


Definition of molecular weight

: the average mass of a molecule of a compound compared to ¹/₁₂ the mass of carbon 12 and calculated as the sum of the atomic weights of the constituent atoms

Examples of molecular weight in a Sentence

Recent Examples on the Web

This movement toward subtlety picked up steam in 2016 with the FDA approval of Juvéderm Volbella XC, which combines multiple molecular weights of hyaluronic acid for a softer fill. Brennan Kilbane, Allure, "Dermatologists Are Now Using Fillers to Simulate Instagram Filters, So I Decided to Try It," 19 Apr. 2018 Once the pulmonary embolism is diagnosed, treatment with intravenous heparin, or injections of low-molecular weight heparin, both blood thinners, is started to treat the clot. Sandy Bauers,, "5 Questions: Lessons from the early death of Maroon 5 manager Jordan Feldstein," 6 Apr. 2018 Dyneema, which is an ultra-high molecular weight polyethylene, is now used in Levi’s. Steff Yotka, Vogue, "Intergalactic Fashion Is Trending on the Runways, But It Has Nothing on the Real Thing," 3 Apr. 2018 The story of the layers is told by the molecular weight of the elements contained in them. Yereth Rosen, Alaska Dispatch News, "Teeth, underwater noise and photo collection examined for clues about Cook Inlet beluga woes," 24 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'molecular weight.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of molecular weight

1860, in the meaning defined above

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The first known use of molecular weight was in 1860

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molecular weight


Medical Definition of molecular weight

: the mass of a molecule that may be calculated as the sum of the atomic weights of its constituent atoms

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