\Cro*ton"ic\ (kr?-t?n"?k), a.
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}.