molecular weight

noun

: 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

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With that in mind, a formula with two different molecular weights of hyaluronic acid can penetrate more optimally and promote longer-lasting hydration. Jessie Quinn, People.com, 1 Nov. 2024 There are four different molecular weights of hyaluronic acid in this formula, meaning the ingredient can penetrate the skin to different depths and create a volumizing effect at multiple levels of the skin. Emily Orofino, Allure, 29 Oct. 2024 Its ultra-fine mist is infused with niacinamide for a shine-free finish and sodium hyaluronate—a derivative of hyaluronic acid that's smaller in molecular weight—to penetrate the surface layer of the skin for a hydrated, dewy finish. Jennifer Hussein, Allure, 3 Oct. 2024 Other larger peptides are able to repair damage at the surface of the cuticle, but a smaller molecular weight allows our peptides to penetrate all the way into the medulla, or the deepest parts of the hair’s core. Celia Shatzman, Forbes, 1 Oct. 2024 See all Example Sentences for molecular weight 

Word History

First Known Use

1860, in the meaning defined above

Time Traveler
The first known use of molecular weight was in 1860

Dictionary Entries Near molecular weight

Cite this Entry

“Molecular weight.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/molecular%20weight. Accessed 21 Nov. 2024.

Kids Definition

molecular weight

noun
: the weight of a molecule equal to the sum of the weights of the atoms contained in it

Medical Definition

molecular weight

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

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