māˈniac noun

1. A person affected with (a) mania
2. A madman
3. A keen enthusiast

1. Affected by or relating to (a) mania
2. Raving mad

Forming nouns and adjectives

maniacal /mə-nīˈə-kl/ adjective

maniˈacally adverb

manic /manˈik/ adjective

1. Of or affected by mania
2. Ludicrously busy or energetic (informal)

manˈically adverb

manˈic-depressˈive noun

A person suffering from manic-depressive psychosis (also adjective)

manic-depressive psychosis noun

A form of mental illness characterized by phases of depression and elation, either alone or alternately, with lucid intervals