BULB
Bulb, n. Etym: [L. bulbus, Gr. bulbe.]

1. (Bot.)

Defn: A spheroidal body growing from a plant either above or below the ground (usually below), which is strictly a bud, consisting of a cluster of partially developed leaves, and producing, as it grows, a stem above, and roots below, as in the onion, tulip, etc. It differs from a corm in not being solid.

2. (Anat.)

Defn: A name given to some parts that resemble in shape certain
bulbous roots; as, the bulb of the aorta. Bulb of the eye, the
eyeball.
— Bulb of a hair, the "root," or part whence the hair originates.
— Bulb of the spinal cord, the medulla oblongata, often called
simply bulb.
— Bulb of a tooth, the vascular and nervous papilla contained in
the cavity of the tooth.

3. An expansion or protuberance on a stem or tube, as the bulb of a thermometer, which may be of any form, as spherical, cylindrical, curved, etc. Tomlinson.

BULB
Bulb, v. i.

Defn: To take the shape of a bulb; to swell.

BULBACEOUS
Bul*ba"ceous, a. Etym: [L. bulbaceus. See Bulb, n.]

Defn: Bulbous. Jonson.