Meaning of memory cell

mem'ory cell"

Pronunciation: [key]
  1. any small, long-lived lymphocyte that has previously encountered a given antigen and that on reexposure to the same antigen rapidly initiates the immune responseor proliferates and produces large amounts of specific antibodythe agent of lasting immunity.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.