This page provides all possible meanings and translations of the word psychosocial. Wiktionary(0.00 / 0 votes)Rate this definition: Freebase(0.00 / 0 votes)Rate this definition: For a concept to be psychosocial means it relates to one's psychological development in, and interaction with, a social environment. The individual needs not be fully aware of this relationship with her or his environment. It was first commonly used by psychologist Erik Erikson in his stages of social development.