noun The bulb-shaped underground portion of a plant such as a tulip, consisting of a shortened stem and many fleshy scale leaves, from which the rest of the plant may be regrown.
noun The medulla oblongata.
noun Any solid object rounded at one end and tapering on the other, possibly attached to a larger object at the tapered end.
the bulb of the aorta
noun A light bulb (not necessarily bulbous in shape).
an incandescent bulb
noun A bulbous protuberance at the forefoot of certain vessels to reduce turbulence.