bulb

[buhlb] /bʌlb/
noun
1.
Botany.
  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, especially at the end of a cylindrical object:
the bulb of a thermometer.
3.
Electricity.
  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.
Anatomy. any of various small, bulb-shaped structures or protuberances:
olfactory bulb; bulb of urethra.
5.
medulla oblongata.
6.
Building Trades. a rounded thickening at the toe of an angle iron or tee.
7.
Nautical. a cylindrical or spherical prominence at the forefoot of certain vessels.
8.
Photography. a shutter setting in which the shutter remains open as long as the shutter release is depressed. Symbol: B.
Origin
1560-70; < Latin bulbus < Greek bolbós onion, bulbous plant
Related forms
bulbed, adjective
bulbless, adjective
Examples from the web for bulb
  • The common incandescent light bulb will soon become a lot less common.
  • Two of the switches do nothing, but one of them controls a bulb on the second floor.
  • When prices fall, the bulb will dim and the country could be plunged back into darkness.
  • In standard flash photography, a bulb on the camera releases a burst of light.
  • In containers, plant in porous mix with bulb tip near the surface.
  • It's still spring, and bulb planting season is months away.
  • The bulb foliage may fade, but the rocks act as place markers forever.
  • Every spring bulb is a perfect package, containing everything necessary for a splendid spring flower show.
  • Rosemary bushes are full of blue flowers, bulb blossoms are starting to crack open, and spring blooms are budded up ready to go.
  • Unscrew a light bulb that uses a lot of electricity and replace it with one that uses much less.
British Dictionary definitions for bulb

bulb

/bʌlb/
noun
1.
a rounded organ of vegetative reproduction in plants such as the tulip and onion: a flattened stem bearing a central shoot surrounded by fleshy nutritive inner leaves and thin brown outer leaves Compare corm
2.
a plant, such as a hyacinth or daffodil, that grows from a bulb
3.
See light bulb
4.
a rounded part of an instrument such as a syringe or thermometer
5.
(anatomy) a rounded expansion of a cylindrical organ or part, such as the medulla oblongata
6.
Also called bulbous bow. a bulbous protuberance at the forefoot of a ship to reduce turbulence
Word Origin
C16: from Latin bulbus, from Greek bolbos onion
Word Origin and History for bulb
n.

1560s, "an onion," from Middle French bulbe (15c.), from Latin bulbus "bulb, bulbous root, onion," from Greek bolbos "plant with round swelling on underground stem." Expanded by 1800 to "swelling in a glass tube" (thermometer bulb, light bulb, etc.).

bulb in Medicine

bulb (bŭlb)
n.
A globular or fusiform anatomical structure or enlargement.

bulb in Science
bulb
(bŭlb)
A rounded underground storage organ that contains the shoot of a new plant. A bulb consists of a short stem surrounded by fleshy scales (modified leaves) that store nourishment for the new plant. Tulips, lilies, and onions grow from bulbs. Compare corm, rhizome, runner, tuber.

Slang definitions & phrases for bulb

bulb

noun

dim bulb (1960s+)