rotenone
noun
ro·te·none
ˈrō-tə-ˌnōn 
: a crystalline insecticide C23H22O6 obtained from the roots of several tropical plants (such as a derris) that is highly toxic to fish but is of low toxicity to warm-blooded animals and is used especially in home gardens
Examples of rotenone in a Sentence
Recent Examples on the Web
After a few more spot treatments with rotenone, Soda Butte was declared brook trout free.
—
Travis Hall, Field & Stream, 24 Aug. 2023
Over the course of one week in 2015, state and federal agencies killed 450 brook trout using a broad application of rotenone throughout 38 miles of the Lamar River tributary.
—Travis Hall, Field & Stream, 24 Aug. 2023
As crews finished building the 500-foot dam in 1962, the Utah and Wyoming departments of fish and game poisoned more than 400 miles of the Green River with the chemical rotenone.
—Leia Larsen, The Salt Lake Tribune, 22 July 2023
Studies have shown that copper sulfate, pyrethrins, and rotenone all can be detected on plants after harvest—for copper sulfate and rotenone, those levels exceeded safe limits.
—Christie Wilcox, Discover Magazine, 24 Sep. 2012
The 3- to 7-acre nursery ponds were poisoned with rotenone to kill out any existing fish before the Florida fish were stocked, along with forage species, including bluegill, threadfin shad and fathead minnows.
—Matt Williams, Dallas News, 29 July 2022
The agency treated the slough with the fish killer rotenone on Saturday and Sunday.
—Brandon Loomis, USA TODAY, 19 Sep. 2022
Fisheries biologists regularly apply liquid rotenone in Western streams to rid them of rainbow and other nonnative trout with the goal of restoring native cutthroat trout populations.
—Brian Maffly, The Salt Lake Tribune, 26 Aug. 2021
Applying rotenone in lakes is a much different operation, deploying a powdered form of the chemical with the consistency of flour.
—Brian Maffly, The Salt Lake Tribune, 26 Aug. 2021
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Travis Hall, Field & Stream, 24 Aug. 2023
Over the course of one week in 2015, state and federal agencies killed 450 brook trout using a broad application of rotenone throughout 38 miles of the Lamar River tributary.
—Travis Hall, Field & Stream, 24 Aug. 2023
As crews finished building the 500-foot dam in 1962, the Utah and Wyoming departments of fish and game poisoned more than 400 miles of the Green River with the chemical rotenone.
—Leia Larsen, The Salt Lake Tribune, 22 July 2023
Studies have shown that copper sulfate, pyrethrins, and rotenone all can be detected on plants after harvest—for copper sulfate and rotenone, those levels exceeded safe limits.
—Christie Wilcox, Discover Magazine, 24 Sep. 2012
The 3- to 7-acre nursery ponds were poisoned with rotenone to kill out any existing fish before the Florida fish were stocked, along with forage species, including bluegill, threadfin shad and fathead minnows.
—Matt Williams, Dallas News, 29 July 2022
The agency treated the slough with the fish killer rotenone on Saturday and Sunday.
—Brandon Loomis, USA TODAY, 19 Sep. 2022
Fisheries biologists regularly apply liquid rotenone in Western streams to rid them of rainbow and other nonnative trout with the goal of restoring native cutthroat trout populations.
—Brian Maffly, The Salt Lake Tribune, 26 Aug. 2021
Applying rotenone in lakes is a much different operation, deploying a powdered form of the chemical with the consistency of flour.
—Brian Maffly, The Salt Lake Tribune, 26 Aug. 2021
Cite this Entry
“Rotenone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rotenone. Accessed 2 Jul. 2025.
Copy CitationKids Definition
rotenone
noun
ro·te·none
ˈrōt-ᵊn-ˌōn
: a substance obtained from tropical plants that is usually harmless to warm-blooded animals but is poisonous especially to insects
Medical Definition
rotenone
noun
ro·te·none
ˈrōt-ᵊn-ˌōn
: a crystalline insecticide C23H22O6 that is of low toxicity for warm-blooded animals and is used especially in home gardens
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