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

Among the changes proposed by the Trump EPA are delaying closure and cleanup requirements for active sites and weakening restrictions on coal ash reuse — potentially allowing practices similar to those that led to it being spread throughout Pines. — Christiana Freitag, Chicago Tribune, 13 June 2026

Beyond its luminous core, Messier 77 is also a highly active site of star formation. — Bojan Stojkovski, Interesting Engineering, 10 May 2026

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

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

Word History

First Known Use

1957, in the meaning defined above

Rhymes for active site

• actinolite
• adipocyte
• amphibolite
• anorthosite
• anthophyllite
• aragonite
• carbonatite
• cassiterite
• chalcopyrite
• cristobalite
• crocidolite
• diatomite

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