Crowding refers to a subjective feeling of not having enough space per person or due to the presence of other people.
Other /More definition:
Crowding may also be defined as: 1. a subjective feeling of being overstimulated by a loss of privacy or by the nearness of others, especially when social contact with them is unavoidable;. 2. a person's perception of discomfort in a high-density environment; the subjective feeling that that there are too many people in a given space;. 3. a psychological reaction that occurs when individuals feel that the amount of space available to them is insufficient for their needs.