phosphine

American  

[fos-feen, -fin] / ˈfɒs fin, -fɪn /

noun

Chemistry.

1. a colorless, poisonous, ill-smelling, flammable gas, PH 3 .

2. any of certain organic derivatives of this compound.

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phosphine British  

/ ˈfɒsfiːn /

noun

1. a colourless flammable gas that is slightly soluble in water and has a strong fishy odour: used as a pesticide. Formula: PH 3

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Etymology

Origin of phosphine

First recorded in 1870–75; phosph- + -ine ¹

Explanation

Phosphine is a poisonous gas that has a strong, distinctively fishy smell. Exterminators sometimes use phosphine to kill pests or keep them from infesting shipments of grains. Phosphine is an effective way to kill bedbugs, rats, and other pests, but it can also be very dangerous for humans who are exposed to the toxic substance. The chemical is mainly used in industrial extermination, often to fumigate the goods on container ships, but it's also used in the semiconductor industry and is sometimes an ingredient in flame retardants. People who work with phosphine have to be careful to avoid inhaling it.

Example Sentences

See Examples For:

phosphine

"Proof has been found that this chemical product was used by the hotel," the report added, indicating that there was "solid proof" that the family "died as a result of phosphine gas".

From Barron's ● Nov. 25, 2025

"Understanding the problem with phosphine was one of our first goals."

From Science Daily ● Nov. 9, 2025

The surprising part, however, is not that phosphine was found -- but that it appears absent from other brown dwarfs and gas giant exoplanets where scientists expected it.

From Science Daily ● Nov. 9, 2025

Yet two subsequent scientific investigations failed to replicate the earlier study’s results, suggesting that there was no phosphine as previously thought.

From Salon ● Nov. 24, 2024

Orange.—Eclipse phosphine, immedial orange, pyrogene orange, thion orange, thiogene orange.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 8 "Dubner" to "Dyeing" by Various