- either of two oily, liquid compounds, C20H28O3 or C21H28O5, used as insecticides.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- either of two similar organic compounds found in pyrethrum and used as insecticides. Formulas: C 20 H 28 O 3 (cinerin I), C 21 H 28 O 5 (cinerin II)
C20: from Latin ciner-, cinis ashes + -in