indigo

Indigotin is a synonym of indigo.

As nouns the difference between indigo and indigotin

is that indigo is a purplish-blue colour while indigotin is a dark blue compound that is the principal dye in indigo.

As an adjective indigo

is having a deep blue colour.

As nouns the difference between indigo and hendigo

is that indigo is anil, indigo (plant) while hendigo is a combination of henna and indigo, used as a hair dye.