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long-term memory

noun
  1. information stored in the brain and retrievable over a long period of time, often over the entire life span of the individual (contrasted with short-term memory).

Origin of long-term memory

First recorded in 1965–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for long-term memory

long-term memory

noun
  1. psychol that section of the memory storage system in which experiences are stored on a semipermanent basisCompare short-term memory
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
long-term memory in Medicine

long-term memory

n.
  1. The phase of the memory process considered the permanent storehouse of retained information.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.