Definition of castor bean in US English:

castor bean


  • 1The seed of the castor-oil plant. It contains a number of poisonous compounds, especially ricin, as well as castor oil.

    • ‘At this point, no one has exhibited symptoms of exposure to ricin, a deadly derivative of the castor bean.’
    • ‘The poison, derived from the castor bean plant, is extremely deadly in tiny amounts.’
    • ‘In young castor bean plants, this time constant is around 15 ms, therefore making this plant particularly appropriate for spectroscopic NMR micro-imaging studies.’
    • ‘Known as ricin, the compound's toxicity is one reason why American farmers no longer grow this crop extensively - even though a lucrative market exists for the castor bean's unique oil.’
    • ‘In castor bean and soybean seeds, vacuolar processing enzymes were detected in the protein bodies and probably associated with the conversion of proproteins to their corresponding mature forms in vacuoles.’
    • ‘The main line of investigation is reportedly an effort to conduct DNA testing to determine the geographic origin of the castor bean plant from which the ricin is derived.’
    • ‘But they say the poison derived from castor beans is most suited to being used in an assassination attempt on a leading public figure rather than a mass attack on a civilian target.’
    • ‘If the castor beans are ingested, the toxin can cause stomach irritation, diarrhoea, abdominal pain, increased heart rate, profuse sweating, collapse, convulsions and death.’
    • ‘One initial test conducted at the scene came back positive for the presence of ricin, a toxin made from the castor bean.’
    • ‘Researchers are attacking the castor bean problem on the genetic front as well.’
    • ‘In contrast to soybean (where assimilates are stored in the cotyledons), the primary storage tissue in castor bean seeds is the endosperm, a maternal tissue which releases assimilates apoplasmically to the growing seedling.’
    • ‘Those three components together tell you that you have mashed castor beans, not ricin.’
    • ‘This order included conifers such as pines, firs, and cypresses (the distinction between true flowers and conifer cones was not clear), but also included a few true flowering plants, such as the castor bean.’
    • ‘That was rubbish; they found a few castor beans in some flat.’
    • ‘Although ricin can be purified through chemical extraction processes from castor beans, the material found in these jars was far less toxic than purified ricin.’
    • ‘It's made from castor beans, hardly an obvious materiel.’
    • ‘The poison is derived from the seeds and pods of the castor bean plant and may be inhaled, ingested or injected.’
    • ‘Ricin, which is derived from the castor bean plant, can kill within days.’
    1. 1.1North American The castor-oil plant.
      • ‘And so it was back to the nursery for red daylilies and castor beans, burgundy-leafed cannas and other jewel-colored plants to go along with it.’
      • ‘Even taller is a planting of castor beans Ricinus communis.’
      • ‘Similar findings were reported for castor bean and pea, supplied with as the sole nitrogen source.’
      • ‘Bengal Tiger, with its bold stripes of green and gold is a real show stopper, but I have a sneaky fondness for red flowered cannas with burgundy leaves mixed with the bold bluish burgundy foliage of the castor bean.’
      • ‘The roots of castor bean responded to K + limitation with an enhanced biosynthesis and deposition of ABA.’
      • ‘A few weeks later, Gavin returned with a flat of castor bean seedlings.’
      • ‘Two extremely toxic plants are castor bean and precatory bean or rosary pea (Abrus).’
      • ‘Be very cautious about growing poisonous plants, like castor bean or hellebore, in readily accessible areas.’
      • ‘Called bi ma zi in herbology, castor bean is a bitter, acrid herb that reduces swelling and clears obstruction.’
      • ‘Herbs such as the castor bean and poison hemlock, which killed ancient Greek philosopher Socrates, are toxic.’


castor bean

/ˈkastər bēn/