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definitions

afterload

[ăf′tər-lōd′]
n.
  1. The arrangement of a muscle so that it lifts a weight from an adjustable support or works against a constant opposing force to which it is not exposed when at rest.
  2. The load or force thus encountered.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.