Bulb
//ˈbʌlb// noun, verb
noun, verb ·Common ·High school level
Definitions
Noun
- 1 The bulb-shaped underground portion of a plant such as a tulip, consisting of a shortened stem and many fleshy scale leaves, from which the rest of the plant may be regrown.
"the plants which grow in the earth from seed or bulbs."
- 2 a rounded part of a cylindrical instrument (usually at one end) wordnet
- 3 The medulla oblongata. dated
- 4 electric lamp consisting of a transparent or translucent glass housing containing a wire filament (usually tungsten) that emits light when heated by electricity wordnet
- 5 Any solid object rounded at one end and tapering on the other, possibly attached to a larger object at the tapered end.
"the bulb of the aorta"
Show 7 more definitions
- 6 a rounded dilation or expansion in a canal or vessel or organ wordnet
- 7 Any solid object rounded at one end and tapering on the other, possibly attached to a larger object at the tapered end.; A light bulb (not necessarily bulbous in shape).
"an incandescent bulb"
- 8 lower or hindmost part of the brain; continuous with spinal cord; (‘bulb’ is an old term for medulla oblongata) wordnet
- 9 A bulbous protuberance at the forefoot of certain vessels to reduce turbulence.
- 10 a modified bud consisting of a thickened globular underground stem serving as a reproductive structure wordnet
- 11 An onion. obsolete
- 12 anything with a round shape resembling a teardrop wordnet
Verb
- 1 To take the shape of a bulb; to swell. intransitive
Example
More examples"Thomas Edison invented the light bulb."
Etymology
Etymology tree Ancient Greek βολβός (bolbós)bor. Latin bulbusder. English bulb Inherited from Middle English bulb, bolbe, from Latin bulbus (“bulb, onion”), from Ancient Greek βολβός (bolbós, “plant with round swelling on underground stem”).
Related phrases
More for "bulb"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.