-
- To save this word, you'll need to log in.
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
Recent Examples on the Web
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
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.
Word History
First Known Use
1860, in the meaning defined above
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 30 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
More from Merriam-Webster on molecular weight
Britannica.com: Encyclopedia article about molecular weight
Love words? Need even more definitions?
Merriam-Webster unabridged
Share