Final answer:
A person who has deep feelings of despondency is likely experiencing major depression, a mental illness characterized by prolonged periods of sadness.
Step-by-step explanation:
A person who has deep feelings of despondency is likely experiencing major depression, a mental illness characterized by prolonged periods of sadness. People with major depression may experience symptoms such as intense sadness, mental slowing, loss of concentration, pessimistic worry, agitation, and feelings of self-depreciation. Physical changes such as weight loss, decreased libido, and disruption of hormonal circadian rhythms may also occur.