Medical Dictionary

indigo

noun in·di·go \ˈin-di-ˌgō\
plural in·di·gos or in·di·goes

Medical Definition of INDIGO

1
a :  a blue dye obtained from indigo plants (as Indigofera tinctoria of Africa and India, I. anil of South America, and I. auriculata of Arabia and Egypt) b :  the principal coloring matter C16H10N2O2 of natural indigo usually synthesized as a blue powder with a coppery luster—called also indigotin
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