frenetic

Etymology

From Middle English frenetik (also frentik, frentyk, frantike > modern English frantic), from Old French frenetike, from Latin phreneticus, from Ancient Greek φρενητικός (phrenētikós, “delirious”), from φρενῖτις (phrenîtis, “delirium”), from φρήν (phrḗn, “mind”). Doublet of frantic and phrenitic. Etymologically, initial stress would be expected (compare the syncopic form phrentic); the modern pronunciation with stress on the second syllable is due to the influence of other words ending in -etic such as phonetic and sympathetic.

adj

1. Fast, harried; having extreme enthusiasm or energy.
   After a week of working at a frenetic pace, she was ready for Saturday.
2. (obsolete) Mentally deranged, insane.
3. (obsolete, medicine) Characterised by manifestations of delirium or madness.

noun

1. One who is frenetic.