bulb

American  

[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. B

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bulb British  

/ 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

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bulb Scientific  

/ bŭlb /

1. 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.

2. Compare corm rhizome runner tuber

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Other Word Forms

• bulbed adjective
• bulbless adjective

Etymology

Origin of bulb

1560–70; < Latin bulbus < Greek bolbós onion, bulbous plant

Example Sentences

So many cartoons depict great ideas using light bulbs that we’ve forgotten many of the greatest ideas come about from long deliberation and careful winnowing.

From Los Angeles Times

Also called the ajo lily, it grows from a deep bulb, has long, wavy-edged leaves and is pollinated by sphinx moths.

From Los Angeles Times

Laser light differs from the light produced by bulbs or LEDs because its electromagnetic waves move in perfect sync.

From Science Daily

The “Village of Lights” and its roughly 500,000 bulbs went dark for a weekend.

From The Wall Street Journal

It has a sac-like cup at the base of its bulb that is usually found under the soil — a sign it is in the Amanita genus which can be dangerous, Diaz said.

From Los Angeles Times

Related Words

• corn