Thuja plicatis

from The Collaborative International Dictionary of English v.0.48
thujone \thu"jone\ (th[=u]"j[=o]n), n.
   An oil, {C10H16O}, the chief constituent of cedar leaf oil
   (thuja oil), which is obtained from the northern white cedar
   (arbor vitae, {Thuja occidentalis}) or the western Red Cedar
   ({Thuja plicatis}). It is a stimulant similar to camphor. It
   is also called {thujol}, {thuyol}, {absinthol}, {thuyone},
   {tanacetol}, and {tanacetone}. --Stedman.
   [PJC]
    

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