Noun

• S: (n) institution, establishment (an organization founded and united for a specific purpose)
• S: (n) institution (an establishment consisting of a building or complex of buildings where an organization for the promotion of some cause is situated)
• S: (n) institution (a custom that for a long time has been an important feature of some group or society) "the institution of marriage"; "the institution of slavery"; "he had become an institution in the theater"
• S: (n) initiation, founding, foundation, institution, origination, creation, innovation, introduction, instauration (the act of starting something for the first time; introducing something new) "she looked forward to her initiation as an adult"; "the foundation of a new scientific society"
• S: (n) mental hospital, psychiatric hospital, mental institution, institution, mental home, insane asylum, asylum (a hospital for mentally incompetent or unbalanced person)