institution in WordNet English dictionary

1. a hospital for mentally incompetent or unbalanced person
   mental hospital  psychiatric hospital  mental institution  institution  mental home  insane asylum  asylum 
   
2. 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"
   initiation  founding  foundation  institution  origination  creation  innovation  introduction  instauration 
   
3. an organization founded and united for a specific purpose
   institution  establishment 
   
4. an establishment consisting of a building or complex of buildings where an organization for the promotion of some cause is situated
   institution 
   
5. 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"
   institution