Final answer:
Gynecomastia is the development of breast tissue in a male. It occurs due to an imbalance of hormones and can happen at different stages of life.
Step-by-step explanation:
Gynecomastia is the development of breast tissue in a male. It is characterized by an enlargement of the mammary glands, resulting in breast growth. This condition is caused by an imbalance of hormones, specifically a decrease in testosterone or an increase in estrogen. Gynecomastia can occur during various stages of life, such as infancy, puberty, and later in adulthood.