- The definition of a bulb is an underground bud of a plant, or something resembling its rounded or elongated shape.
- An example of a bulb is an onion.
- An example of a bulb is an electric light bulb.
A man holding a bulb from which a flowering plant is sprouting.Licensed from iStockPhoto
- an underground bud that sends down roots and consists of a very short stem covered with leafy scales or layers, as in a lily, onion or hyacinth
- a corm, tuber, or tuberous root resembling a bulb, as in a crocus, dahlia or cyclamen
- any plant that grows from a bulb
- anything shaped like a bulb; rounded thing or enlarged part: an electric light bulb, the bulb of a syringe
- an enlargement on some tissues, organs, or tubes, as at the root of a hair
- Obsolete medulla oblongata
Origin: Middle English ; from Classical Latin bulbus ; from Classical Greek bolbos
Used by arrangement with John Wiley & Sons, Inc.
- Botany a. A short, modified, underground stem surrounded by usually fleshy modified leaves that contain stored food for the shoot within: an onion bulb; a tulip bulb.b. A similar underground stem or root, such as a corm, rhizome, or tuber.c. A plant that grows from a bulb.
- A rounded projection or part: the bulb of a syringe.
- An incandescent lamp or its glass housing.
- Anatomy A rounded dilation or expansion of a canal, vessel, or organ.
Origin: Latin bulbus, from Greek bolbos, bulbous plant.
bulb - Medical Definition
bulb - Science Definition
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