bulb: Meaning and Definition of

bulb

1. a usually subterranean and often globular bud having fleshy leaves emergent at the top and a stem reduced to a flat disk, rooting from the underside, as in the onion and lily.
2. a plant growing from such a bud.
2. any round, enlarged part, esp. at the end of a cylindrical object: the bulb of a thermometer.
1. the glass housing, in which a partial vacuum has been established, that contains the filament of an incandescent electric lamp.
2. an incandescent or fluorescent electric lamp.
4. any of various small, bulb-shaped structures or protuberances: olfactory bulb; bulb of urethra.
5. See
6. a rounded thickening at the toe of an angle iron or tee.
7. a cylindrical or spherical prominence at the forefoot of certain vessels.
8. a shutter setting in which the shutter remains open as long as the shutter release is depressed. Symbol: B