closed system

American  

noun

Thermodynamics.

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

---

closed system Scientific  

1. A physical system that does not interact with other systems. A closed system obeys the conservation laws in its physical description.

2. Also called isolated system

3. Compare open system

---

Etymology

Origin of closed system

First recorded in 1895–1900

Compare meaning

How does closed-system compare to similar and commonly confused words? Explore the most common comparisons:

• open system vs. closed system

Example Sentences

Even if you’re using an employer’s closed system, just don’t copy and paste your notes.

From The Wall Street Journal • Feb. 24, 2026

Or the TCM could be in an isolated chamber, evacuated of air, which is known as a closed system.

From Science Daily • Nov. 19, 2024

But Tesla cars could be ready because they operate on a closed system, Tal said, where the company makes both the EVs and the chargers.

From Scientific American • Apr. 27, 2023

"It's a closed system that solves the problem. The tickets can't be resold."

From BBC • Jan. 25, 2023

Normally, nuclear reactors use purified water, which runs through a closed system to ensure that none of the water from the reactor can get out—and that no impurities can get in.

From "Meltdown" by Deirdre Langeland