Manic

google

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late Middle English: via late Latin from Greek, literally ‘madness’, from mainesthai ‘be mad’.

wiktionary

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mania +‎  -ic; Ancient Greek μανικός(manikós). 

etymonline

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manic (adj.)

"pertaining to or affected with mania," 1902, from mania + -ic. The clinical term manic depressive also is from 1902; manic depression is first attested 1903. An older name for it was circular insanity (1857), from French folie circulaire (1854).