hydrofluoricacid

hy·dro·fluor·ic acid (hī'drō-flo͝orʹĭk, -flôrʹ-, -flōrʹ-) n.

A colorless, fuming, corrosive, dangerously poisonous aqueous solution of hydrogen fluoride, HF, used to etch or polish glass, pickle certain metals, and clean masonry.

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