phosphodiesterase
noun
phos·pho·di·es·ter·ase
ˌfäs-(ˌ)fō-dī-ˈe-stə-ˌrās 
-ˌrāz
: a phosphatase (as from snake venom) that acts on diesters (such as some nucleotides) to hydrolyze only one of the two ester groups
Examples of phosphodiesterase in a Sentence
Recent Examples on the Web
These undeclared ingredients are part of the phosphodiesterase (PDE-5) inhibitor drug class, which the FDA only approved for use as prescriptions under healthcare provider supervision.1234
Potential Risks and Side Effects
Honey packs contain hidden tadalafil or sildenafil.
—
Ross Phan, Verywell Health, 1 July 2025
This compound has been found to inhibit an enzyme called phosphodiesterase type 5 (PDE5), which is similar to how prescription medications like Viagra work.
—Amber Smith, Discover Magazine, 13 Oct. 2023
The research was funded by Cancer Research UK and the Medical Research Council, which found that phosphodiesterase type 5, or PDE5 inhibitors, can help shrink tumors in the esophagus.
—Joshua Hawkins, BGR, 6 Oct. 2022
To do so, the active ingredient in the drug inhibits an enzyme called phosphodiesterase 5 (PDE5) found in blood vessel walls.
—Sandee Lamotte, CNN, 7 Feb. 2020
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Ross Phan, Verywell Health, 1 July 2025
This compound has been found to inhibit an enzyme called phosphodiesterase type 5 (PDE5), which is similar to how prescription medications like Viagra work.
—Amber Smith, Discover Magazine, 13 Oct. 2023
The research was funded by Cancer Research UK and the Medical Research Council, which found that phosphodiesterase type 5, or PDE5 inhibitors, can help shrink tumors in the esophagus.
—Joshua Hawkins, BGR, 6 Oct. 2022
To do so, the active ingredient in the drug inhibits an enzyme called phosphodiesterase 5 (PDE5) found in blood vessel walls.
—Sandee Lamotte, CNN, 7 Feb. 2020
Cite this Entry
“Phosphodiesterase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phosphodiesterase. Accessed 18 Sep. 2025.
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phosphodiesterase
noun
phos·pho·di·es·ter·ase
-dī-ˈes-tə-ˌrās, -ˌrāz
: a phosphatase (as from snake venom) that acts on diesters (as some nucleotides) to hydrolyze only one of the two ester groups
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