Homesickness is a feeling of unhappiness a person may have when away from home or from familiar surroundings or people. It has a similar meaning to the word nostalgia.
People sometimes become homesick when they travel. They miss their own home and desperately want to go back. Children may often feel homesick, especially when they are away from their parents for the first time. Usually these feelings will go away as one gets used to the new environment, but sometimes homesickness can make a person depressed.
People may easily feel homesick if they travel to an environment in which the culture is very difficult to what they are used to, and especially if a foreign language is being spoken. Children who are sent away to boarding school will very often feel homesick.