: an enzyme that hydrolyzes ATP
especially : one that hydrolyzes ATP to ADP and inorganic phosphate

Examples of ATPase in a Sentence

Recent Examples on the Web
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Burns Calories Coffee may help burn calories because of caffeine's effect on the muscle protein called sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA). Lauren O'Connor, Health, 16 June 2025

Word History

First Known Use

1946, in the meaning defined above

Time Traveler
The first known use of ATPase was in 1946

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Cite this Entry

“ATPase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ATPase. Accessed 30 Jun. 2025.

Medical Definition

: an enzyme that hydrolyzes ATP
especially : one that hydrolyzes ATP to ADP and inorganic phosphate

called also adenosine triphosphatase

Last Updated: - Updated example sentences
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