bulb

noun
\ ˈbəlb How to pronounce bulb (audio) \
plural bulbs

Definition of bulb

1a : 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

Illustration of bulb

Illustration of bulb

bulb 1a: 1 hyacinth, 2 onion, 3 tulip, 4 lily

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Other Words from bulb

bulbed \ ˈbəlbd How to pronounce bulbed (audio) \ adjective
flasks with bulbed necks
bulblike \ ˈbəlb-​ˌlīk How to pronounce bulblike (audio) \ or bulb-like adjective
… a large underground rhizome, a bulblike growth that extends massive roots from its underside. — Elizabeth Schneider

Examples of bulb in a Sentence

the bulb of the thermometer

Recent Examples on the Web

Add 2 stalks celery, 1 Bartlett pear, 1 bulb fennel, and 1 scallion (all thinly sliced) and toss to combine. Woman's Day Kitchen, Woman's Day, "Pear & Walnut Salad," 21 Dec. 2018 Some of these products use LEDs or have no replaceable bulbs at all. Ashley Carman, The Verge, "Philips new Hue lights cover your entire home, inside and out," 10 Aug. 2018 Detectives say Marlene Warren, 40, answered the door to her home in the Aero Club community on May 26, 1990, to accept a bouquet and two balloons from a clown wearing an orange wig, a red bulb nose, gloves and a smile painted on its white face. Chuck Weber, Sun-Sentinel.com, "Evidence photos shed light on notorious killer clown case," 4 July 2018 Garlic: Those stray pieces and half bulbs that are probably stowed away in the butter shelf of the fridge are perfect additions to the hot charcoal. Chuck Blount, San Antonio Express-News, "Add a little more flavor to your grill with fragrant ingredients," 2 July 2018 If the problem is harsh lighting, think about solutions: Different overhead bulbs? New York Times, "How to Deal With Misguided Job Inquiries," 22 June 2018 Their decor has come as the biggest shock to Raque, who describes the setting as a fancy tea room, with its Edison bulb lights and beveled mirrors. Bailey Loosemore, The Courier-Journal, "80/20 at Kaelin's wants to honor restaurant's history - not imitate it," 24 May 2018 The 73-foot tall neon and bulb sign atop the 12-story, distinctively curved building at 2107 Grand Blvd. has been dark for years. Matt Campbell, kansascity, "Iconic Western Auto sign to relight the Kansas City skyline | The Kansas City Star," 22 May 2018 Park staff removed 13 streetlights and switched many bulbs to light-emitting diodes (LED). Helena Oliviero, ajc, "Plan your trip: A guide to the Okefenokee swamp," 2 July 2018

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.

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First Known Use of bulb

15th century, in the meaning defined at sense 1a

History and Etymology for bulb

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

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Learn More about bulb

Dictionary Entries near bulb

bukshi

Bul

Bulawayo

bulb

bulbaceous

bulb angle

bulbar

Statistics for bulb

Last Updated

7 Mar 2019

Look-up Popularity

Time Traveler for bulb

The first known use of bulb was in the 15th century

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More Definitions for bulb

bulb

noun

English Language Learners Definition of bulb

: 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

noun
\ ˈbəlb How to pronounce bulb (audio) \

Kids Definition of 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

bulb

noun
\ ˈbəlb How to pronounce bulb (audio) \

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

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More from Merriam-Webster on 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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