Lignum Vitae, an evergreen tree native to tropical America from Panama to the West Indies. The lignum vitae grows to 30 feet (9 m) tall and bears featherlike leaves and purplish-blue flowers. It is cultivated as an ornamental in South America, southern California, and Florida.

The wood of the lignum vitae is of commercial importance, being used in butcher blocks and pulleys, and in ship construction. It is the heaviest of all commercial woods and is composed of layers of fiber that cross each other diagonally, making it tough and hard. The tree yields guaiac, a hard resin with medicinal properties. The name lignum vitae (Latin for “tree of life”) refers to the resin's former use in rheumatism and tonsillitis medications. The resin is occasionally used in lozenges to soothe sore throats.

Lignum vitae is Guaiacum officinale of the caltrop family, Zygophyllaceae.