casing vs housing

casing and housing both are nouns.

Word	Noun	Adjective	Verb	Adverb
casing	Yes	No	No	No
housing	Yes	No	No	No

As nouns, housing is a hypernym of casing; that is, housing is a word with a broader meaning than casing:

casing: the housing or outer covering of something
housing: a protective cover designed to contain or support a mechanical component

casing (noun)	housing (noun)
the enclosing frame around a door or window opening	structures collectively in which people are housed
the housing or outer covering of something	a protective cover designed to contain or support a mechanical component
the outermost covering of a pneumatic tire	stable gear consisting of a decorated covering for a horse, especially (formerly) for a warhorse