a.1.(Chem.) Pertaining to, or designating, a brown resinous substance resembling tannin, and extracted from the henna plant; as, hennotannic acid.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
The leaves produce hennotannic acid (especially lawsone) and a green oil, a resin soluble in ether and alcohol.
Henna brown colouring constituents are of a resinoid fracture having chemical properties similar to tannins, hence the name hennotannic acid.