Bipolar illness, also known as bipolar disorder, is a mental health condition characterized by fluctuating moods. It is a condition that affects millions of people worldwide and can lead to severe disruptions in daily life. There are several synonyms for bipolar illness, including manic-depressive illness, manic-depression, and bipolar affective disorder. Other terms used to describe this condition include bipolar spectrum disorder and cyclic mood disorder. These synonyms are often used interchangeably and refer to the same condition. Understanding the symptoms and prevalence of bipolar illness is essential for individuals and loved ones dealing with this challenging mental health condition.