a dye, such as indigo, that is applied by first reducing it to its leuco base, which is soluble in alkali, and then regenerating the insoluble dye by oxidation in the fibres of the material
Derived forms
vat-dyed (ˈvat-ˌdyed)
adjective
vat dye in American English
a colorfast dye made soluble for application to cloth, then oxidized and thus rendered insoluble in the cloth