Definition of placentation in English:



Anatomy Zoology
  • 1[mass noun] The formation or arrangement of a placenta or placentae in a woman's or female animal's uterus.

    • ‘Functional roles for relaxin within human reproductive tissues have also been implicated during placentation, parturition, and lactation.’
    • ‘Although the exact etiology for placenta accreta and increta is not known, it is thought that damage to the decidua basalis may lead to abnormal placentation and its sequelae.’
    • ‘Most embryo clones fail to develop, and pregnancies terminate spontaneously due to fetal abnormalities or difficulties with placentation.’
    • ‘The presence of an apparently unique type of lymphocyte in the uterus at implantation and during early placentation is intriguing.’
    • ‘Notably, in the three mammalian groups, equids, murids, and peromyscids, in which placental development of interspecific hybrids was analyzed to date, placentation defects were observed.’
    1. 1.1Botany The arrangement of the placenta or placentae in the ovary of a flower.
      • ‘The ovary is superiorly positioned with basal placentation.’
      • ‘These are distinguished by characters of the bracts, placentation, inflorescence type, cytology and distribution.’
      • ‘Both genera were transferred to Flacourtiaceae by Warburg and later by Gilg on the basis of a number of morphological characters, such as a trimerous ovary with parietal placentation and anthers with longitudinal dehiscence.’
      • ‘The berries in the most derived clade (Olmstead et al.'s subfamily ‘Solanoideae’) are all morphologically similar, with two carpels, axile placentation and mostly lenticular seeds.’
      • ‘Salicornioideae seeds have a basal placentation, congruent with other representatives of the Chenopodiaceae.’