plural bulbs
1
a
: 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
bulbed adjective
flasks with bulbed necks
bulblike adjective
or bulb-like
… a large underground rhizome, a bulblike growth that extends massive roots from its underside. Elizabeth Schneider

Illustration of bulb

Illustration of bulb
  • 1 hyacinth
  • 2 onion
  • 3 tulip
  • 4 lily

Examples of bulb in a Sentence

the bulb of the thermometer
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
There are other sizes of bulbs in this shape, like C7, which is slightly smaller than the C9. Halee Miller Van Ryswyk, Better Homes & Gardens, 7 Dec. 2024 The lockers for the Dallas Cowboys cheerleaders are more like mini dressing rooms, complete with full mirrors, bulb lighting, and hooks for uniforms. Elise Taylor, Vogue, 26 Nov. 2024 Riebe says some even have a special touch—a hole in the back of the house to accommodate a Christmas bulb to illuminate the windows. Nicole Letts, Southern Living, 26 Nov. 2024 The bottom line is the fall bulb planting process is really quite accommodating. Paul Cappiello, The Courier-Journal, 15 Nov. 2024 See all Example Sentences for bulb 

Word History

Etymology

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

First Known Use

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

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

Dictionary Entries Near bulb

Cite this Entry

“Bulb.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bulb. Accessed 21 Dec. 2024.

Kids Definition

bulb

noun
1
a
: an underground resting stage of a plant (as an onion or tulip) consisting of a short stem base bearing one or more buds enclosed in overlapping leaves
b
: a fleshy structure (as a tuber or corm) resembling a bulb in appearance or function
2
: a rounded object or part shaped more or less like a bulb
a flashlight bulb

Medical Definition

bulb

noun
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

More from Merriam-Webster on bulb

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