Definition of bulb in English:


See synonyms for bulb

Translate bulb into Spanish


  • 1A rounded underground storage organ present in some plants, notably those of the lily family, consisting of a short stem surrounded by fleshy scale leaves or leaf bases, lying dormant over winter.

    Compare with corm, rhizome

    ‘Snowdrops hate having their roots disturbed, but dividing them in spring allows their roots to recover and gives the leaves time to feed the bulb before they become dormant later in summer.’
    • ‘No matter what your climate, be sure to water planted bulbs throughout the winter.’
    • ‘It is a good time to buy and plant conifers and evergreens, summer-flowering bulbs and dahlia tubers.’
    • ‘If the winters are harsh, then cover the bulbs with straw or leaves.’
    • ‘The fresh weight of roots, bulbs and leaf bases (when the bulbing ratio was < 2) was measured every week or every month.’
    • ‘Treating lily bulbs with cytokinin hormones can mean early flowers and more of them.’
    • ‘The buds are already dormant within the bulbs and the difference in size will affect the size of the flower.’
    • ‘Many of their early wildflowers and spring-blooming bulbs go dormant by Memorial Day, so they shrug off the dry summers.’
    • ‘Diet varies with the season but consists primarily of seeds, bulbs, leaves, berries, and some insects.’
    • ‘Not far from West Bank Park, local residents planted daffodil bulbs in the green surround of Holgate Windmill last year.’
    • ‘On the left, a bulb of Fritillaria; bulbs are underground fleshy storage leaves wrapped tightly around the stem, such as in onion and garlic.’
    • ‘When sold and planted in fall, bulbs are in a dormant state that makes them very easy to handle and ship.’
    • ‘Those who received potted lilies can plant the bulbs outside in an area with bright light or in morning sun and afternoon shade.’
    • ‘After 12 weeks of storage three of these bulbs were planted to determine the quality of the flowers.’
    • ‘Voles have been known to travel tunnels developed by moles to gain access to flower bulbs and other plant roots.’
    • ‘Checks with Norfolk police revealed that the pair were known to have been involved in the theft of wild flowers, plants and bulbs, which were then re-sold to the public.’
    • ‘Glutamyl peptidase activity has been detected in leaves, roots, and bulbs of growing onions, but not in dormant bulbs of variety Southport White Globe.’
    • ‘Although they have their favourite plants, they will eat almost anything that's not too tough and leathery including leaves, stems, bulbs, root vegetables, even flowers.’
    • ‘In the chilled bulb, the floral stem is visible in the centre of the bulb, while the leaves and flower have grown outside the sensitive volume of the detection coil.’
    • ‘A wide range of monocots produce bulbs of modified leaves which store food over the winter.’
    tuber, corm, rhizome
    View synonyms
    1. 1.1A plant grown from a bulb.
      ‘I also have two small bulbs which are one piece rather than divided into cloves - they grew from bulbils and if replanted will grow into proper divided bulbs next year.’
      • ‘Garlic grows in bulbs with even cloves enclosed in a white or pink skin.’
      • ‘It is also difficult to identify garlics by appearance, since cloves from the same bulb grow differently in different locations.’
      • ‘Like its more comely cousin, garlic grows from a bulb, sending a tall green stalk up from the earth to catch sunlight and to flower.’
      • ‘The cottage style garden in the Adelaide Hills features a collection of hellebores in a range of colours as well as bulbs and winter flowering shrubs like Magnolia.’
      • ‘Lachenalias in general are small fleshy bulbs with two upright, opposite leaves.’
      • ‘Transfer the fish to the serving plate on top of the grilled fennel and sprinkle over any reserved fronds/leaves from the fennel bulb.’
      • ‘Add the venison bones, garlic bulb, celeriac, carrots, and bacon and sauté until the bacon fat is rendered, about five minutes.’
      • ‘The bulbs should be round, firm and white, with feathery green shoots.’
      • ‘They have thin stalks that make braiding easy and the bulbs ' white skins are quite attractive.’
      • ‘If there are too many outside layers of skin on the garlic bulbs, pull them off first.’
      • ‘Intact garlic bulbs contain alliin, which has no medicinal properties.’
      • ‘Each bulb contains a fist full of cloves of varying sizes.’
      • ‘Its cloves, of which a bulb contains six to more than two dozen, have little smell when whole but release a notoriously strong one when crushed.’
      • ‘Fritillaria bulb is known to contain sixteen different alkaloids that comprise up to 0.4% of the herb by weight.’
      • ‘Remove from the heat and strain through a fine mesh sieve, reserving the garlic bulb separately.’
      • ‘The most elegant is Tulipa Purissima, pure white and perfectly shaped bulbs tinged with lime green, the ideal spring flower for a formal town garden of clipped bay and box.’
      • ‘The strong wind may pull the onion leaves down, thus resulting in nutrients being directed toward the onion bulb.’
      • ‘So we pumped some flavor in here by adding some of the fennel bulb and some celery, as well.’
  • 2A light bulb.

    ‘The reason for this is, if replacement bulbs have a different voltage or wattage to the original set, your lights will be dimmer or brighter and this will overload the light chain and permanently damage the set.’
    • ‘Events through the week include a light bulb amnesty at which normal light bulbs can be exchanged for low-energy bulbs donated by Yorkshire Electricity.’
    • ‘Also, that you know the wattage of the bulb and your electric rates.’
    • ‘But two days before Friday's grand switch-on ceremony vandals removed bulbs from the display and smashed them in the street.’
    • ‘In all but the biggest gardens, provided you have reasonably high wattage bulbs and a powerful enough transformer, a simple 12-volt system is enough.’
    • ‘An electrician wired them for low-voltage bulbs and linked them on timers so they go on at dusk.’
    • ‘I want to be able to buy Thai spices in the market town and I want my local electrical shop to sell 500 different types of low-voltage bulbs.’
    • ‘In December 1878 and February 1879 he demonstrated his first incandescent electric bulbs.’
    • ‘But unlike ordinary incandescent bulbs, they don't have a filament that will burn out, and they don't get especially hot.’
    • ‘Compact fluorescents use a third to a quarter of the electricity of standard incandescent bulbs, and last up to 10 times longer.’
    • ‘If the illumination source does not include a spectrum close to that of incandescent bulbs or the sun, then the color of objects will be different than what we are accustomed to.’
    • ‘The white lights are chosen because of Norwegian tradition (electrical bulbs being the twentieth-century equivalent of candlelight).’
    • ‘In the days when all traffic lights consisted of incandescent bulbs behind a plastic filter, the heat produced by the lamps was not much of an issue for designers.’
    • ‘Turning on a light switch applies a sudden surge to bulbs and transformers, shortening the life of both.’
    • ‘The church was lit by half-a-dozen electric bulbs (arranged in two rows of three like the dots on a six-point domino).’
    • ‘When electricity debuted, people did not know what to do with it, other than light a bulb, but this changed once they realized its unlimited potential.’
    • ‘It was the first to do away with unsightly wires by using the arm structure as an electrical, low voltage conductor to ignite the halogen bulb.’
    • ‘The recycler also reclaims the glass and metal found in the thousands of burned-out bulbs the refinery replaces each year.’
    • ‘He also added that if someone was smashing thousands of bulbs into a garbage bin then mercury levels in that person's blood would go up.’
    • ‘Thus argon is used to fill tungsten filament bulbs and fluorescent tubes: no matter how hot the filament gets, argon will not react with it.’
  • 3An expanded part of a glass tube such as that forming the reservoir of a thermometer.

    ‘It was a narrow glass tube with a bulb at the bottom.’
    • ‘Crookes's tube consisted of a glass bulb, from which most of the air had been removed, encasing two metal plates called electrodes.’
    • ‘Yesterday, all the bulbs in my galileo thermometer were up the top.’
    • ‘The instrument, consists of two glass bulbs united by a narrow neck.’
    • ‘A glass bulb, then, is used to keep oxygen away from the filament.’
    • ‘The grains of sand teeter on the edge of the glass bulb.’
    • ‘A wet bulb thermometer is simply a thermometer with the bulb wrapped in moist muslin.’
    • ‘Another gadget, a simple glass bulb with four small vanes inside, the faces of each painted black or white.’
    • ‘The result is an hourglass shaped vessel, with both the upper and lower bulbs holding 2 oz.’
    • ‘They consisted of a curved U-tube filled with mercury attached to a bulb containing creosote.’
    1. 3.1A hollow flexible container with an opening through which the air can be expelled by squeezing, such as that used to fill a syringe.
      ‘Nicola took out a small medicine bottle with a bulb syringe, and began with delicate squeezes of the bulb to collect the moisture that gathered at the corners of the child's eyes.’
      • ‘Gently put the compressed bulb into the open nostril.’
      • ‘Release pressure (let the air back in) on the bulb until the nose is clear.’
      • ‘Use a suction bulb or put some of the warm salt water in the cup of your hand to sniff it up one nostril at a time.’
      • ‘Empty the contents onto a tissue by squeezing the bulb rapidly while holding it upside down.’
      • ‘Multiple delivery methods and devices have been studied but not compared, including bottles or pots, bulb syringes, inhalers, and nebulizers.’
      • ‘Droppers with rubber bulbs should not be kept with the essential oil bottle as the highly concentrated oil can turn the rubber bulb into gum.’
      • ‘A bulb syringe to be used to remove mucous from the mouth/nose’
      • ‘Air cast pressure was changed by manually increasing air volume with a BP bulb; pressure was continuously monitored with a mercury manometer.’
      • ‘Release the bulb, holding it in place while it suctions the mucus from your baby's nose.’
      • ‘Using a bulb syringe and saline nose drops can also help to keep a baby's nose clear.’
      • ‘The scrub person drapes the infant warmer with sterile terry cloth towels and ensures that there are two bulb syringes and cord clamps in the warmer.’
      • ‘Labels that do not adhere adequately to the bulb syringe could increase the risks of leaving foreign bodies in the surgical wound.’
      • ‘The third time I arranged things just so, manoeuvred the syringe into my ear, reaching over the top of my head with my left hand, and squeezed the tiny rubber bulb gently.’
      • ‘Gently suction out the nose with an ear bulb every few hours.’
      • ‘The infant developed mild respiratory distress at delivery that resolved with bulb and orogastric suction and administration of free-flow oxygen.’
      • ‘If your baby is having trouble sucking, try using a rubber suction bulb to help clear his or her nose before each feeding.’
      • ‘Dry the syringe bulb and store it in a cup or container.’
      • ‘You would get less mercury in the dropper than you would water if you squeezed the bulb equally in both cases.’
      • ‘Blow out the dust with compressed air, canned air, a blow-out bulb (ear syringe), or a vacuum in the blower mode.’
    2. 3.2A spheroidal dilated part at the end of an anatomical structure.
      ‘For the sense of smell, odors are processed in an area of the brain called the olfactory bulb.’
      • ‘If it is exactly in the midline, it may be the duodenal bulb, the pylorus, or the distal antrum.’
      • ‘An anomalous carotid artery or jugular bulb may present in a similar fashion.’
      • ‘Muscular sphincters may exist anteriorly or posteriorly in the pharyngeal bulb.’
      • ‘The offactory bulb in the nose and the pleasure center of the brain are connected by a direct sensory pathway.’
      • ‘The middle-right arrow shows tissue similar to the uterus and ejaculatory bulb cortex.’
      • ‘We report a case of Brunner gland hamartoma of the duodenal bulb with unusual histologic features.’
      • ‘A skin biopsy from one of the patches found many empty hair bulbs without any inflammation or scarring.’
      • ‘Venous hums may be heard in patients with hypertension or abnormally high placement of the jugular bulb.’
      • ‘He observed long processes of sensory neurons coursing into the brain from the retina and olfactory bulb.’
      • ‘An upper gastrointestinal tract endoscopy showed mucosal telangiectasia in the stomach and duodenal bulb.’
      • ‘When light reaches your hair follicles, it temporarily generates enough heat to destroy the follicles and bulbs.’
      • ‘These neuroendocrine tumors arise from the adventitia of the jugular bulb or the neural plexus within the middle ear space.’
      • ‘Loss of gar - 3 function speeds up the repolarization of the terminal bulb muscles and shortens action potentials.’
      • ‘Similar tumors may arise from neighboring areas, including the jugular bulb, the middle ear, and the mastoid portion of the temporal bone.’
      • ‘An additional set of 10, usually monociliary gland cells opens anteriorly and outside of the pharyngeal bulb into the mouth cone lumen.’
      • ‘The lower esophagus and duodenal bulb are common sites of gastric metaplasias occurring as a protective response to the injurious action of gastric acid.’
      • ‘Glomus tumor is a vascular neoplasm arising from the paraganglia around the carotid bifurcation, the jugular bulb, or the tympanic arteries.’
      • ‘Loss of gar - 3 function results in shortened action potentials and brief muscle contractions in the pharyngeal terminal bulb.’
      • ‘Everything from the beginning of the esophagus to the posterior of the anterior bulb was considered ‘foregut.’’





Late Middle English via Latin from Greek bolbos ‘onion, bulbous root’.