Henna
A plant dye from the leaves of the henna plant, used for centuries to colour hair red and auburn.
Also: mehndi
Henna is a dye made from the dried, powdered leaves of the henna plant, Lawsonia inermis. Mixed into a paste and left on the hair for hours, it stains the hair red, copper or auburn and coats the strand. It has been used across South Asia, the Middle East and North Africa for thousands of years, on hair, nails and skin as mehndi. Henna is mixed with indigo for darker shades. Pure henna can react badly with later chemical colour, so stylists ask about it.