bell jar

American  

noun

1. a bell-shaped glass jar or cover for protecting delicate instruments, bric-a-brac, or the like, or for containing gases or a vacuum in chemical experiments.

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bell jar British  

noun

1. a bell-shaped glass cover used to protect flower arrangements or fragile ornaments or to cover apparatus in experiments, esp to prevent gases escaping

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Etymology

Origin of bell jar

First recorded in 1875–80

Example Sentences

They used precision-milled steel to construct the capsule and designed a special bell jar to surround it in a layer of dry air, protecting the inside from the moist soil of the American northeast.

From The Wall Street Journal • Apr. 21, 2026

Again: What works within the humid environment under a bell jar or inside a narrow-mouthed lab flask is quite different from what flourishes in an open bowl or an uncovered fish tank.

From Seattle Times • Dec. 20, 2021

Esther Greenwood’s account of her year in the bell jar is as clear and readable as it is witty and disturbing.

From New York Times • Oct. 21, 2021

I feel my head is encased in some kind of — like I said, I write about the bell jar.

From Salon • Jan. 19, 2020

How did I know that someday—at college, in Europe, somewhere, anywhere—the bell jar, with its stifling distortions, wouldn't descend again?

From "The Bell Jar" by Sylvia Plath