BULB, noun [Latin bulbus, a bulb or round root.] A round body, applied to many objects. But in botany, it is appropriately a bud formed under ground, upon or near the roots of certain herbaceous plants, which are hence called bulbous plants, as the tulip, onion and lily. The bulb under ground is what the bud is upon the stem or branches, a hybernacle or winter receptacle of a future plant, containing the plant in embryo, covered with a bark or rind, generally consisting of scales placed over each other, to defend the tender rudiments of the plant from cold and other external injuries. A bulb is scaly in the lily, solid in the tulip, coated in the onion, and jointed in the tuberous moschatel.

BULB, verb intransitive To bulb out is to project or be protuberant. [Little used.]