california sycamore: tall tree of Baja California having deciduous bark and large alternate palmately lobed leaves and ball-shaped clusters of flowers
physical entity: an entity that has physical existence
selenium: a toxic nonmetallic element related to sulfur and tellurium; occurs in several allotropic forms; a stable grey metallike allotrope conducts electricity better in the light than in the dark and is used in photocells; occurs in sulfide ores (as pyrite)