bulb

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noun \ ˈbəlb \

Definition of bulb

1 a :a resting stage of a plant (such as the lily, onion, hyacinth, or tulip) that is usually formed underground and consists of a short stem base bearing one or more buds enclosed in overlapping membranous or fleshy leaves

b :a fleshy structure (such as a tuber or corm) resembling a bulb in appearance

c :a plant having or developing from a bulb

2 :a bulb-shaped part; specifically :a glass envelope enclosing the light source of an electric lamp or such an envelope together with the light source it encloses

3 :a rounded or swollen anatomical structure

4 :a camera setting that indicates that the shutter can be opened by pressing on the release and closed by ending the pressure

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bulbed

play \ˈbəlbd\ adjective

See bulb defined for English-language learners

See bulb defined for kids

Examples of bulb in a Sentence

the bulb of the thermometer

Recent Examples of bulb from the Web

The backyard is propped with Brimfield finds — seats made from rusty milk cans, vintage signs — and above, a web of industrial light bulbs.

— penelope green, New York Times, "In the ’90s, We Had ‘Friends.’ Now They Call It Co-Living.," 23 Aug. 2017
Aside from having a head shaped like a light bulb, Miller is probably, most definitely a white nationalist.

— sydney scott, Essence.com, "Stephen Miller And His White Nationalist Views Are Being Considered To Replace Scaramucci," 7 Aug. 2017
The round bulb is about the size of a baseball and packs 250 lumens with high and low settings.

— mark maynard, sandiegouniontribune.com, "Helping hands for DIY in the garage," 2 Aug. 2017
Sale of iris and daffodil bulbs and plants from local garden clubs.

— The Courier-Journal, "Home and garden events July 29 and beyond," 26 July 2017
Regular waxes make the hair finer and the bulb smaller.

— loni venti, Cosmopolitan, "Everything You Need to Know Before Getting a Brazilian Wax," 17 July 2017
At present, most regions reach a wet-bulb maximum of 26 or 27 degrees Celsius; the true red line for habitability is 35 degrees.

— david wallace-wells, Daily Intelligencer, "When Will the Planet Be Too Hot For Humans? Much, Much Sooner Than You Imagine.," 9 July 2017
Kings, queens and governments from around the world contributed bulbs, plants and statuary representing their country's culture, such as a Chinese bridge, and woodcarvings from Norway.

— joan dittmann, Post-Tribune, "Native American heritage on display in Michigan City," 5 July 2017
The LA tattooer took to Instagram last night to show off Lucy's design — a tiny vintage light bulb on the back of her arm, just an inch or so above her elbow.

— kaleigh fasanella, Allure, "Lucy Hale Reveals New Light Bulb Tattoo on Doctor Woo’s Instagram," 29 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'bulb.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Illustration of bulb

Origin and Etymology of bulb

Middle English, from Latin bulbus, from Greek bolbos bulbous plant

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First Known Use: 15th century

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BULB Defined for English Language Learners

bulb

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noun

Definition of bulb for English Language Learners

: a rounded part of some plants that is under the ground and that grows into a new plant during the growing season
: a part that has a rounded shape

BULB Defined for Kids

bulb

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noun \ ˈbəlb \

Definition of bulb for Students

1 :light bulb

2 :a dormant stage of a plant that is formed underground and consists of a very short stem with one or more flower buds surrounded by special thick leaves

3 :a plant structure (as a tuber) that is somewhat like a bulb

4 :a rounded object or part

the bulb of a thermometer

Medical Dictionary

bulb

play

noun \ ˈbəlb \

medical Definition of bulb

1 :a rounded dilation or expansion of something cylindrical

the bulb of a thermometer

; especially :a rounded or pear-shaped enlargement on a small base

the bulb of an eyedropper

2 :a rounded part: as

a :a rounded enlargement of one end of a part — see bulb of the penis, bulb of the vestibule, end bulb, hair bulb, olfactory bulb

b :medulla oblongata; broadly :the hindbrain exclusive of the cerebellum

c :a thick-walled muscular enlargement of the pharynx of certain nematode worms

Learn More about bulb

Spanish Central: Translation of bulb Nglish: Translation of bulb for Spanish speakers Britannica English: Translation of bulb for Arabic speakers Britannica.com: Encyclopedia article about bulb

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bulb

Definition of bulb

bulbed

From the M-W Editors

Examples of bulb in a Sentence

Recent Examples of bulb from the Web

Illustration of bulb

Origin and Etymology of bulb

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BULB Defined for English Language Learners

bulb

Definition of bulb for English Language Learners

BULB Defined for Kids

bulb

Definition of bulb for Students

Medical Dictionary

bulb

medical Definition of bulb

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