And when they were come into the house, they saw the young child with Mary his mother, and fell down, and worshipped him: and when they had opened their treasures, they presented unto him gifts; gold, and frankincense and myrrh.

Here's the same passage from the Latin Vulgate:

et intrantes domum invenerunt puerum cum Maria matre eius et procidentes adoraverunt eum et apertis thesauris suis obtulerunt ei munera aurum tus et murram

You'll note that there are several interesting things about this passage. First, despite the carols, and the Henry Van Dyke Story of The Other Wise Man, and all the traditions surrounding Christmas, we have no reference to there being three wise men, not in this passage, and not elsewhere in the New Testament. We know that there was more than one, since all the verbs are plural. It's reasonable to assume that the three gifts, gold, frankincense, and myrrh, were brought by three different men, but it's not clear from the text that there were three, specifically.

Frankincense is from Middle English frank with the word encens. Frank is from Old French franc and means "free, pure"— it's the same word as Modern English "frank," as in "to speak frankly." Encens is the French word that spawned Modern English incense (AHD). In case you're curious, frankincense is in fact burned as incense. It's also still used today, not only as incense but as an ingredient in perfumes. It's made from the resin of trees native to Asia and Africa, of the genus Boswellia. The tree is deliberately scored, which produces a thick, resinious sap. The sap is allowed to dry, and then the hard nodules of resin are collected. The resin can be burned as is, but it's often rendered into an oil that can be burned, or used in the manufacture of perfumes. At times, frankincense was more valuable by weight than gold. It was often used as a preservative as well. Frankincense has a pungent, musky, slightly resinous scent, one that's not exactly like anything else, though it often does remind people of specific perfumes.

Myrrh is another aromatic resin, from trees of the Commiphora species, natives of Inda, Arabia, and eastern Africa, though it's a more sticky, resinous gum that's usually exuded naturally from injured trees, and then collected by harvesters to regularly inspect groves of the trees. Myrrh is sometimes called "Balm of Gilead," because of other Biblical references. Etymologically speaking, Modern English Myrrh is derived from Middle English mirre, via Old English myrrha, itelf derived from the Greek murrha via Latin. Ultimately, though myrrh, or Greek murrha is of Semitic ancestry. The Greeks borrowed the Semitic root mrr, which means "To be (come) bitter"; myrrh is noticeably bitter in taste, which is still used as a way of verifying that the resinous nuggets brought to be weighed for use in perfumes and incense are in fact the genuine article.