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 The wet bulb globe thermometer factors in more details such as sun angle, cloud cover and wind speed. Allison Chinchar And Haley Brink, CNN, "Miami broke its all-time heat record for June, but no warnings were issued. Here's why," 5 July 2020 Prices range from $18.99 for a mini bulb all the way to $89.99 for two Downlight bulbs. Jason Cipriani, CNN Underscored, "All the smart lights and speakers to light up your home for the Fourth of July," 1 July 2020 All of the vegetables on your list with the exception of fennel (which needs cooler temps in fall to bulb) and kale (see note below) thrive in full sunlight. oregonlive, "Ask an expert: Happy vegetable gardens get 8-12 hours of full sun daily," 27 June 2020 Swap out the bulb in your living room lamp to keep the bugs off your TV at night. Travel + Leisure, "The 11 Best Bug-zapping Lamps for Summer," 26 June 2020 Researchers who study the olfactory bulb know that distinct patterns of neural activity in the bulb correspond to different scents. Grace Huckins, Wired, "Scientists Taught Mice to Smell an Odor That Doesn’t Exist," 25 June 2020 Compatible with any medium-base bulb up to 75 W (not included). Mark Heim | Mheim@al.com, al, "Outdoor furniture sale offers up to 50 percent off deals on sectionals, patio umbrellas, lighting," 24 June 2020 In midspring and early summer, scratch low-nitrogen fertilizer into the soil around each bulb. Andrea Beck, Better Homes & Gardens, "What Are Orienpet Lilies and Why You Need Them in You Garden," 23 June 2020 The bulb, like the ground, has a positive charge, which attracted the negative ions from the balloon. Rebecca Renner, National Geographic, "Don’t let children just watch the weather—have them create it instead.," 10 June 2020

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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Time Traveler for bulb

Time Traveler

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

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Statistics for bulb

Last Updated

8 Jul 2020

Cite this Entry

“Bulb.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bulb. Accessed 9 Jul. 2020.

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More Definitions for bulb

bulb

noun
How to pronounce bulb (audio)

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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