Frankincense. A vegetable resin, brittle, glittering, and of a bitter taste, used in Hebrew offerings and sacrifices. Exodus 30:34-36. It burns for a long time with a steady flame. It is obtained by successive incisions in the bark of a tree called Arbor thuris. The first incision yields the purest and whitest resin, while the product of the after incisions is spotted with yellow, and loses its whiteness altogether as it becomes old. The Hebrews imported their frankincense from Arabia. Isaiah 60:6; Jeremiah 6:20.