bulb
[buhlb]
- Botany.
- 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.
- Electricity.
- 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
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Origin of bulb
1560–70; < Latin bulbus < Greek bolbós onion, bulbous plant
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for bulb
Contemporary Examples
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.
By May, its bulb can grow as big as two centimeters, and turns pink and then a deep red as it matures.
Historical Examples
I shall tell you the day when you are to put the bulb in the ground.
The Black TulipAlexandre Dumas (Pere)
Do you mean to say that the bulb has now been in the ground for six days?
The Black TulipAlexandre Dumas (Pere)
Amaryllis Formosissima was in bloom in one week after I planted the bulb.
The Mayflower, January, 1905Various
And yet the bulb has not only an honourable character—it has a sort of sacred history.
StoryologyBenjamin Taylor
The stem is white, squamulose, bulb rugulose, ring superior and entire.
The Mushroom, Edible and OtherwiseM. E. Hard
bulb
- 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
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Word Origin
C16: from Latin bulbus, from Greek bolbos onion
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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.).
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Online Etymology Dictionary, © 2010 Douglas Harper
bulb
(bŭlb)- A globular or fusiform anatomical structure or enlargement.
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The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
bulb
[bŭlb]
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.