Definition of raphe in English:



  • 1Biology Anatomy
    A groove, ridge, or seam in an organ or tissue, typically marking the line where two halves fused in the embryo.

    • ‘If the variant is bilateral the deviant muscle plate has a raphe in the median line.’
    • ‘Its fibers pass dorsally from an extensive anterior attachment to insert on the pharyngeal raphe, the pharyngeal tubercle of the occipital bone.’
    • ‘They are located close to the median raphe, ventromedial to the hypoglossal nucleus.’
    1. 1.1 The connecting ridge between the two halves of the medulla oblongata or the tegmentum of the midbrain.
      • ‘In rats, the CO2-sensitive neurons of the caudal medullar raphe act during sleep only.’
      • ‘Stimulation of 5 - HT1A receptors in the raphe regulates serotonin synthesis and release.’
      • ‘The second pathway arises from the median raphe and enervates the hippocampus and appears to mediate resilience and adaptation to stress.’
      • ‘Because most medullary raphe neurons that project to motoneurons are inhibited by vagal afferents.’
      • ‘Second, there is a midbrain trigger, perhaps in serotonergic neurons of the dorsal raphe.’
  • 2Botany
    A longitudinal ridge on the side of certain ovules or seeds.

    • ‘The raphe is a slightly depressed area on the opposite side of the hilum from the micropyle.’
    1. 2.1 A longitudinal groove in the valve of many diatoms.
      • ‘Through the raphe, the living diatom secretes mucilage, with which it may attach to a substrate or move by gliding over the substrate.’


Mid 18th century: modern Latin, from Greek rhaphē ‘seam’.