Definitions

1. noun

a usually rounded or oval body of tissue or a structure that produces light, as a light bulb or the reproductive part of a plant, such as a tulip or a lily

“The electrician replaced the light bulb in the chandelier.”

2. noun

the rounded tip or base of a cane, sword, or pen

“He held the pen in his hand with the bulb of the nib pointing downwards.”

3. verb

to swell or become swollen

“The bruise began to bulb at the edges.”

4. verb

to produce or emit a light, often in the form of a globe

“The city began to bulb with twinkling lights.”