The term DYE SOURCE can be summarized by two crossword solutions: HENNA (5 letters) and ANIL (4 letters). HENNA is a natural dye made from the leaves of the HENNA plant, which is native to tropical and subtropical regions of Africa, Asia, and Australia. ANIL is a synthetic dye derived from coal tar, which is a byproduct of the coal industry. Both dyes are used in a variety of applications, including cosmetics, fabrics, and food coloring.