phosgene
Concise Oxford English Dictionary © 2008 Oxford University Press:
phosgene /ˈfɒzdʒiːn/
▶noun Chemistry a poisonous gas formerly used in warfare. [COCl2.]
– origin C19: from Gk phōs ‘light’ + -gen, with ref. to its original production by the action of sunlight on chlorine and carbon monoxide.
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