What term is used to describe a mental disorder with symptoms of low mood and low energy?

The term that best describes a mental disorder characterized by symptoms of low mood and low energy is depression. Depression is a mood disorder that significantly impacts a person's emotional state, causing persistent feelings of sadness, hopelessness, and a lack of energy or motivation. These symptoms can affect daily functioning and can vary in intensity.

The understanding of depression is contextualized within a broader spectrum of mental health disorders. Anxiety involves excessive worry or fear, which is distinct from the low mood associated with depression. Bipolar disorder, while it can include low moods, also features episodes of mania, making it different from unipolar depression. Schizophrenia encompasses symptoms such as delusions and hallucinations, which are not associated with the low mood and energy seen in depression. Thus, recognizing depression as the condition linked with prolonged low mood and low energy aligns with established psychological definitions and diagnostic criteria.