- 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.
- a plant growing from such a bud.
- any round, enlarged part, especially at the end of a cylindrical object: the bulb of a thermometer.
- the glass housing, in which a partial vacuum has been established, that contains the filament of an incandescent electric lamp.
- an incandescent or fluorescent electric lamp.
- Anatomy. any of various small, bulb-shaped structures or protuberances: olfactory bulb; bulb of urethra.
- medulla oblongata.
- Building Trades. a rounded thickening at the toe of an angle iron or tee.
- Nautical. a cylindrical or spherical prominence at the forefoot of certain vessels.
- Photography. a shutter setting in which the shutter remains open as long as the shutter release is depressed. Symbol: B
Origin of bulb
Examples from the Web for bulb
So, at the Home Depot in Connecticut, a 40-watt bulb costs $4.97, and a 60-watt bulb costs $6.97.
In 25,000 hours a regular 75-watt bulb would use $262.50 of electricity.
The 40-watt bulb costs $9.97 and the 60-watt bulb retails for $12.97.
Specifically, the law said a bulb should provide 100 watts of brightness while using 72 watts or less.The Best Green Idea in Obama’s Climate-Change Speech
June 25, 2013
By May, its bulb can grow as big as two centimeters, and turns pink and then a deep red as it matures.The Wonderful World of Ramps
April 26, 2011
I shall tell you the day when you are to put the bulb in the ground.
Do you mean to say that the bulb has now been in the ground for six days?
Amaryllis Formosissima was in bloom in one week after I planted the bulb.The Mayflower, January, 1905
And yet the bulb has not only an honourable character—it has a sort of sacred history.Storyology
The stem is white, squamulose, bulb rugulose, ring superior and entire.The Mushroom, Edible and Otherwise
M. E. Hard
- 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 leavesCompare corm
- a plant, such as a hyacinth or daffodil, that grows from a bulb
- See light bulb
- a rounded part of an instrument such as a syringe or thermometer
- anatomy a rounded expansion of a cylindrical organ or part, such as the medulla oblongata
- Also called: bulbous bow a bulbous protuberance at the forefoot of a ship to reduce turbulence
Word Origin and History for bulb
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.).
- A globular or fusiform anatomical structure or enlargement.