What is pertaining to, or designating, an acid C11H20O2, homologous with acrylic acid, and obtained as a white crystalline substance by the distillation of castor oil called?

undecylenic — Pertaining to, or designating, an acid C11H20O2, homologous with acrylic acid, and obtained as a white crystalline substance by the distillation of castor oil. (Webster's 1913.)

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