n :  an essential oil from orange peel or orange flowers: as  a  :  a yellow to deep orange oil obtained from the peel of the sweet fruit of the common cultivated orange (Citrus sinensis) and used chiefly as a flavor and perfume - called also sweet orange oil   b  :  a similar but bitter pale yellow or yellowish brown oil from the peel of the fruit of the sour orange (Citrus aurantium) - called also bitter orange oil  .
 
 
 
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