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

In this state, she says, “wherever I sat … I would be sitting under the same glass bell jar, stewing in my sour air.”

From New York Times • Oct. 21, 2021

I feel like I'm in a weird bell jar, like I say in the book.

From Salon • Jan. 19, 2020

I’ve had several unpleasant dreams where I’m encased in one of Gran’s glass paperweights or trapped beneath the bell jar that houses her arrangement of dried flowers and dead butterflies.

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin