institution vs nuthouse

institution and nuthouse both are nouns.

Word	Noun	Adjective	Verb	Adverb
institution	Yes	No	No	No
nuthouse	Yes	No	No	No

As nouns, nuthouse is a hyponym of institution; that is, nuthouse is a word with a more specific, narrower meaning than institution:

institution (noun)	nuthouse (noun)
the act of starting something for the first time; introducing something new	pejorative terms for an insane asylum
an establishment consisting of a building or complex of buildings where an organization for the promotion of some cause is situated
a hospital for mentally incompetent or unbalanced person
a custom that for a long time has been an important feature of some group or society
an organization founded and united for a specific purpose