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 leavesb : a fleshy structure (such as a tuber or corm) resembling a bulb in appearancec : 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
bulbedplay \ˈbəlbd\ adjective
Examples of bulb in a Sentence
the bulb of the thermometer
Recent Examples of bulb from the Web
Yes: the science behind climate change is older than the light bulb.
Add 1 tablespoon olive oil to skillet; stir in 1 large bulb fennel, cut into 1/4-inch thick sticks.
Its broadcasting booth is illuminated by a single glowing bulb, and its walls are covered in egg-carton-like soundproofing baffles.
If the bulb or ballast is nearing the end of its life span, go ahead and replace it.
In the space of 21/2 hours at Sherwood Gardens on Saturday morning, the Ames family pulled some 267 tulip bulbs out of the ground, much to the delight of everyone, including the people who maintain the North Baltimore park.
The borders are a mix of perennials; bulbs; small shrubs; and vines, including allium, clematis, peonies, lilies, delphinium, hosta and poppies.
And instead of shooting one beam and collecting a single point of data, the Soli chips create a wide radar bulb, designed to be big enough to see your entire hand all at once.
Biodiesel generators will juice all electrical devices at the show, including LED bulbs.
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.
Origin and Etymology of bulb
Middle English, from Latin bulbus, from Greek bolbos bulbous plant
First Known Use: 15th century
BULB Defined for English Language Learners
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
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 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: asa: a rounded enlargement of one end of a part—see bulb of the penis, bulb of the vestibule, end bulb, hair bulb, olfactory bulbb: medulla oblongata; broadly : the hindbrain exclusive of the cerebellumc: a thick-walled muscular enlargement of the pharynx of certain nematode worms
Seen and Heard
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