osmium tetroxide

American  

noun

Chemistry.

1. a crystalline or amorphous, colorless, poisonous compound, OsO 4 , soluble in water, alcohol, and ether: used for microscopic staining, in photography, and as a catalyst in organic synthesis.

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osmium tetroxide British  

noun

1. a yellowish poisonous water-soluble crystalline substance with a penetrating odour, used as a reagent and catalyst in organic synthesis. Formula: OsO 4

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Etymology

Origin of osmium tetroxide

First recorded in 1875–80

Example Sentences

For secondary fixation, we used 2% osmium tetroxide in 1.25% sodium bicarbonate for 2–3 h at room temperature.

From Nature • May 20, 2014