Frankincense is a highly valued source of incense, 'a substance burned for its aromatic smoke', often for ceremonial or therapeutic reasons. It is formed by the resin of trees of the genus Boswellia, native to Somalia and widespread in the southern Arabian peninsula. It is also called '[gum] olibanum' - mostly in technical use, in pharmacy (or apothecaries) and other scientific contexts.
Frankincense formed one of the three gifts brought to the infant Jesus by the Wise Men. The others were gold and myrrh.