He is an 'institution' in local politics. [=he has participated in local politics for such a long time that people consider him to be a regular part of local politics]
She committed herself to a 'mental institution'. [=a hospital for people with mental or emotional problems]
The play has become something of an 'institution' on Broadway.
(..) See you. You said Loki was a night god. Maybe it works at night. I shouId warn you that I don't work personaIIy with reaIIy sick peopIe. There are private institutions for those things. I can arrange for a safe environment for you tonight, if you want. I must see Tina. But what can I do? (..)1994 The Mask