barium fluoride

noun

: a white, solid, crystalline compound BaF₂ that is used as a material in optics (as in lenses) and as a flux (see flux entry 1 sense 6) in some enamels

Barium fluoride would resist the cesium, but it was suitable only for the windows, not for the entire vacuum cell containing the cesium.

—Nick Taylor, Laser, 2000

Word History

First Known Use

1868, in the meaning defined above

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