KJV Dictionary Definition: algum
AL'GUM, n. In scripture, a tree or wood about which the learned are not agreed. The most probably conjecture is that the word denotes gummy or resinous wood in general.
The Vulgate translates it ligna thyina, and the Septuagint, wrought-wood; others, ebony, bravil or pine, and the Rabbins render it coral. It was used for musical instruments, stair cases, &c.
The thyinum is the citron tree, from Mauritania, much esteemed by the ancients for its fragrance and beauty. The almug, almugim, or algumin, or simply gummin is most probably a gummy wood, and perhaps may be the Shittim, often mentioned in Scripture. See 1Kings 10:11.