Dictionary.net

one of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ

One of the nerves of leaves.

One of the chitinous supports, or veins, in the wings of incests.

One of the nerves of leaves.

One of the chitinous supports, or veins, in the wings of incests.

One of the rib-like structures which support the membranous wings of Insects, branches of the tracheal system; a vein.