A frame of lattice work, covered with vines, branches of trees or other plants, for shade; a bower.

In botany, a tree, as distinguished from a shrub. The distinction which Linne makes, that a tree springs up with a bud on the stem, and a shrub not, is found not to hold universally; and the tree, in popular understanding, differs from the shrub only in size. Arbor forms the seventh family of vegetables in Linne’s system. [See Tree.;I .

In mechanics, the principal part of a machine, sustaining the rest. Also the axis or spindle of a machine, as of a crane, or windmill. This in America is called the shaft.