Definition of black measles
1 a
: hemorrhagic measles
b
: rocky mountain spotted fever
2
: a disease of grapevines in California of obscure and undetermined cause characterized by black spotting of the skin of the berries and browning and drying up of the leaf tissue between the veins and often developing suddenly and severely, the leaves dropping and the canes dying back from the tips in a few days — called also
apoplexy
