Definify.com
Webster 1913 Edition
Helianthin
Heˊli-an′thin
,Noun.
[Prob. fr. L.
helianthes
, or NL. helianthus
, sunflower, in allusion to its color.] (Chem.)
An artificial, orange dyestuff, analogous to tropaolin, and like it used as an indicator in alkalimetry; – called also
methyl orange
.