active site

noun

: a region on the surface of an enzyme whose shape permits binding only of a specific molecular substrate that then undergoes catalysis

Examples of active site in a Sentence

Recent Examples on the Web
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The location of the original Govan Old Parish Church was an active site of worship from the 5th century AD until 2007. Leigh Anne Miller, ARTnews.com, 9 Apr. 2026 Researchers introduced a p–n heterojunction catalyst that combines graphitic carbon nitride with a carbon nanofiber network hosting dual cobalt active sites. Prabhat Ranjan Mishra, Interesting Engineering, 6 Feb. 2026 Among the active sites are the Fort Buchanan U.S. Army base, the Camp Santiago Joint Training Center — a Puerto Rico National Guard facility — and the Muñiz Air National Guard Base, attached to the Luis Muñoz Marín International Airport, the island's main hub. Ellie Cook, MSNBC Newsweek, 5 Nov. 2025 At the detention center Alligator Alcatraz remained an active site the morning after Williams’ ruling. Ana Ceballos, Miami Herald, 22 Aug. 2025 See All Example Sentences for active site

Word History

First Known Use

1957, in the meaning defined above

Time Traveler
The first known use of active site was in 1957

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Cite this Entry

“Active site.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/active%20site. Accessed 22 Apr. 2026.

Medical Definition

active site

noun
: a region especially of a biologically active protein (as an enzyme) where catalytic activity takes place and whose shape permits the binding only of a specific reactant molecule

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