apoplexy: [14] The Greek verb apopléssein meant ‘incapacitate by means of a stroke’. It was formed from the prefix apo- ‘away, off’ (here used as an intensive) and the verb pléssein ‘hit’ (source of English plectrum [17] and related to English complain, plangent, plankton, and plague). The derived noun, apoplēxíā, entered English via Latin and Old French. => complain, plague, plangent, plankton, plectrum
apoplexy (n.)
late 14c., "sudden fit of paralysis and dizziness," from Old French apoplexie or directly from Late Latin apoplexia, from Greek apoplexia, from apoplessein "to strike down and incapacitate," from apo- "off" (see apo-), in this case probably an intensive prefix, + plessein "hit" (cognates: plague (n.), also with a root sense of "stricken"). The Latin translation, sideratio, means "disease caused by a constellation."