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definitions

simple absence

[sĭm′pəl]
n.
  1. A brief loss or impairment of consciousness accompanied by the abrupt onset of spasms or twitchings of cephalic muscles that produce a 3 per second pattern of spikes and waves on an electroencephalogram.pure absence
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.