Medical Dictionary

pyrethrin

noun py·re·thrin \pī-ˈrē-thrən, -ˈreth-rən\

Medical Definition of PYRETHRIN

:  either of two oily liquid esters C21H28O3 and C22H28O5 that have insecticidal properties and are the active components of pyrethrum

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May 27, 2015
riot act Hear it
a vigorous reprimand or warning
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