Crotonic
Pronunciation : Cro*ton"ic (kr-tn"k)
Part of Speech : a.
Definition : Defn: Of or pertaining to, or derived from, a plant of the genus Croton, or from croton oil. Crotonic acid (Chem.), a white crystalline organic acid, C3H5.CO2H, of the ethylene, or acrylic acid series. It was so named because formerly supposed to exist in croton oil. Also, any acid metameric with crotonic acid proper. 
Note: The acid characteristic of croton oil is tiglic or tiglinic acid, a derivative of crotonic acid.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder