Frankincense (also known as olibanum, Hebrew: לבונה [levona], Arabic: al-lubān) is an aromatic resin used in incense and perfumes, obtained from trees of the genus Boswellia in the family Burseraceae, particularly Boswellia sacra (syn: B. bhaw-dajiana), B. carterii33, B. frereana, B. serrata (B. thurifera, Indian frankincense), and B. papyrifera. The English word is derived from Old French "franc encens" (i.e., high quality incense).
There are four main species of Boswellia that produce true frankincense. Resin from each of the four is available in various grades. The grades depend on the time of harvesting; the resin is hand-sorted for quality.
The English word frankincense is derived from the Old French expression franc encens meaning high-quality incense. The word franc in Old French meant noble or pure. A popular folk etymology is that this expression derived from the fact that the Frankish people (the forefathers of modern France and Germany) (re-)introduced the spice to Western Europe during the Middle Ages. However, though the ethnic term Frank and the generic term frank are probably related, it is nevertheless the generic term from which the word francincense in fact derives.