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parathion

[par-uh-thahy-on]
noun Chemistry.
  1. a deep-brown to yellow, poisonous liquid, C10H14NO5PS, used as an insecticide.

Origin of parathion

First recorded in 1945–50; para-1 + thi- + -on(e)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for parathion

parathion

noun
  1. a slightly water-soluble toxic oil, odourless and colourless when pure, used as an insecticide. Formula: C 10 H 14 NO 5 PS

Word Origin for parathion

C20: from para- 1 + thio- + -on
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
parathion in Medicine

parathion

[păr′ə-thī′ŏn]
n.
  1. A highly poisonous organic phosphate insecticide that is an irreversible inhibitor of cholinesterase.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.