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closed system

noun Thermodynamics.
  1. a region that is isolated from its surroundings by a boundary that admits no transfer of matter or energy across it.
Compare open system.

Origin of closed system

First recorded in 1895–1900
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
closed system in Science

closed system

  1. A physical system that does not interact with other systems. A closed system obeys the conservation laws in its physical description. Also called isolated system Compare open system.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.