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

Some bulbs and batteries can be taken to Home Depot, Best Buy or Batteries Plus. Devin Kelly, Anchorage Daily News, "How to recycle like a pro in Anchorage," 7 June 2019 Nearly 150 people admired the setting of spring flowering bulbs along wooded trails for an annual event called Daffodil Day, which includes a plant sale that serves as a fundraiser for the cemetery. Jacques Kelly, Howard County Times, "In Ellicott City, a once abandoned cemetery now blooms," 1 Apr. 2018 Squeeze the halved garlic bulbs into the pan and whisk them in for sweet roasted garlic goodness. Alyse Whitney, Bon Appetit, "The Easiest Roast Chicken You'll Ever Make," 19 Feb. 2018 Most of the local Klansmen, plus one Klanswoman—the group’s dim-bulb bomb carrier is the wife of its most obviously psychotic member—are played for laughs. Joe Morgenstern, WSJ, "‘BlacKkKlansman’ Review: Running on Fury," 9 Aug. 2018 These purple, pink, blue, and white bulbs take over the country in lush gardens late April. Elizabeth Gulino, House Beautiful, "Home Depot is Selling Wisteria Trees You Can Plant in Your Backyard—For Just $23," 16 Apr. 2019 This glamorous take on a traditional source of indirect light can accommodate LED or incandescent bulbs. Kathryn O’shea-evans, WSJ, "Goodbye, Showy Chandeliers. Hello, Low-Key Lighting That Transforms Rooms," 25 Jan. 2019 There were amaryllis growing out of the ground, their bulbs the size of soccer balls. Lucia Tonelli, ELLE Decor, "How One Celebrity Florist Brings Flowers into the Home for Spring," 19 Mar. 2019 But for Labor Day, Amazon and Philips Hue are discounting their most popular smart bulbs so you can get started on your smart home—all while still staying within budget. Popular Mechanics Editors, Popular Mechanics, "Light Up Your Space With Amazon's Philips Hue Sale," 31 Aug. 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

13 Jun 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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