c18h34o3

from The Collaborative International Dictionary of English v.0.48

Palmic \Pal"mic\, a. [Cf. F. palmique.] (Chem.)
   Of, pertaining to, or derived from, the castor-oil plant
   ({Ricinus communis}, or {Palma Christi}) and other species of
   the family {Euphorbiaceae}; -- formerly used to designate an
   acid now called {ricinoleic} acid (d-12-hydroxyoleic acid,
   {C18H34O3}). [Obsoles.]
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Ricinoleic \Ric`in*o"le*ic\, a. (Chem.)
   Pertaining to, or designating, a fatty acid analogous to
   oleic acid, obtained from castor oil as an oily substance,
   {C18H34O3} with a harsh taste. Formerly written {ricinolic}
   and formerly referred to as {palmic}.
   [1913 Webster +PJC]

from The Collaborative International Dictionary of English v.0.48

ricinoleic acid \ric`in*o"le*ic ac"id\, n. (Chem.)
   An organic acid ({C18H34O3}) obtained from the castor-oil
   plant ({Ricinus communis}, or {Palma Christi}) and other
   species of the family {Euphorbiaceae}; chemicaly it is
   d-12-hydroxyoleic acid
   ({CH3(CH2)5.CH(OH).CH2.CH=CH.(CH2)7COOH}). Formerly called
   {palmic acid}.
   [1913 Webster +PJC]

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