noun Psychiatry.
- an affective disorder characterized by periods of mania alternating with periods of depression, usually interspersed with relatively long intervals of normal mood.
noun
- a mental health problem characterized by an alternation between extreme euphoria and deep depression
n.
- Any of several mood disorders usually characterized by alternating periods of depression with mania or hypomania.manic-depressive illness
- Any of several mood disorders usually characterized by periods of depression that alternate with mania.
Also known as manic-depressive illness. This psychiatric disorder is marked by periods of euphoric (manic) highs often followed by periods of depression.