What does "thuja" mean?

Thuja: A genus of evergreen trees, thickly branched, remarkable for the distichous arrangement of their branches, and having scalelike, closely imbricated, or compressed leaves. [Written also thuya.] See Thyine wood. Note: Thuja occidentalis is the Arbor vitæ of the Eastern and Northern United States. T. gigantea of North-waetern America is a very large tree, there called red cedar, and canoe cedar, and furnishes a useful timber.