bulb

noun
\ˈbəlb \

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 \ adjective

Examples of bulb in a Sentence

the bulb of the thermometer

Recent Examples on the Web

The bathroom featured a rusty sink, a bare bulb and graffiti. Anne Kadet, WSJ, "Most Restaurants Ace Their Health Inspections, but a Few Still Get Unsavory Grades," 30 Oct. 2018 Take advantage of the fact that hostas emerge late and plant the large open expanses with spring-flowering bulbs and ephemeral wildflowers such as toothworts (Dentaria), spring beauties (Claytonia), and trout lilies (Erythronium). Kris Wetherbee, Good Housekeeping, "How to Grow the Most Stunning Hostas," 7 Aug. 2018 Other perennials, bulbs and ground covers: Bleeding heart (Lamprocapnos spectabilis); sweet woodruff (Galium odoratum); snowdrop (Galanthus nivalis); hellebore (Helleborus); barrenwort (Epimedium); daylily (Hemerocallis); daffodil (Narcissus). Beth Botts, chicagotribune.com, "Many plants die when grown near black walnut trees. These are the ones that survive.," 20 June 2018 Now there’s another shop with Edison bulbs and air plants. Elisa Albert, Longreads, "O, Small-bany!," 7 May 2018 So, after Charles and Camilla came through the doors the night of the ball, beset by flashing bulbs and requests to see the ring, Julia was behind them. Penny Junor, Vanities, "How Camilla Won Over the Queen and Became the Duchess of Cornwall," 28 Mar. 2018 Cut about 1/4 inch off the top of the garlic bulbs and place them on the foil, cut side up. Alexandria Abramian-mott, House Beautiful, "Gale Gand's Recipe for Strata," 3 Jan. 2012 Plant seeds and bulbs for a pretty yard come spring. Wire Services, The Seattle Times, "10 items to check off your fall home to-do list," 15 Oct. 2018 Since overhead lights and windows tend to cause the most glare, using lower wattage bulbs or coverings like blinds may also help. Korin Miller, SELF, "7 Ways to Keep Your Eyes Comfortable If You Work at Computer All Day," 5 Oct. 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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Dictionary Entries near bulb

bukshi

Bul

Bulawayo

bulb

bulbaceous

bulb angle

bulbar

Statistics for bulb

Last Updated

28 Nov 2018

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 \

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 \

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

Comments on bulb

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