Decorative tattoo dye (5)
I believe the answer is:
henna
'decorative tattoo dye' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for henna that I've seen before include "Shrub used for reddish-brown dye" , "Skin and hair dye" , "Red-brown dye used for body decorations" , "Reddish-brown plant dye" , "Beauty aid" .)