bulbus

A bulb.

Pl. bulbi [L.] bulb.

• b. aortae — the swollen, first part of the aorta, between the atria; swollen because of the sinuses above each of the three cusps of the aortic valves.
• b. cordis — the outflow tract of the embryonic heart between the primitive ventricle and the aorta.
• b. glandis — the bulb of the dog's penis; the proximal portion which enlarges greatly during erection and is the part responsible for preventing withdrawal during ejaculation.
• b. oculi — the eyeball.
• b. pili — see hair bulb.
• b. rectricum — a well-organized fibroadipose mass in a muscular envelope into which the retrices (tail feathers of birds) are embedded. It occupies a trough-shaped socket bounded by the caudal vertebrae and the intrinsic tail muscles.