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long-acting

American  
[lawng-ak-ting, long-] / ˈlɔŋˈæk tɪŋ, ˈlɒŋ- /

adjective

Pharmacology.

  1. sustained-release.

long-acting British  

adjective

  1. (of a drug) slowly effective after initial dosage, but maintaining its effects over a long period of time, being slowly absorbed and persisting in the tissues before being excreted Compare intermediate-acting short-acting

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of long-acting

First recorded in 1950–55

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.