Palma Christi
/ˌpalmə ˈkrɪsti/ /ˌpɑːmə ˈkrɪsti/noun
Either of two plants with palmately lobed leaves: †(a) an unidentified medicinal herb, perhaps cut-leaved dead-nettle, Lamium hybridum ( obsolete ); (b) the castor oil plant, Ricinus communis.
Origin
Late Middle English; earliest use found in Practica Phisicalia John of Burgundy. From post-classical Latin palma Christi castor oil plant, also gromwell, species of orchid (1583 in a translation of Dodoens, from 1597 in British sources), lit. ‘palm or hand of Christ’, from the palmate shape of the leaves or tubers from classical Latin palma + Christī, genitive of Christus.