storage room vs stowage

storage room and stowage both are nouns.

Word	Noun	Adjective	Verb	Adverb
storage room	Yes	No	No	No
stowage	Yes	No	No	No

As nouns, storage room and stowage are synonyms defined as:

Other synonyms of storage room include storeroom.

storage room (noun)	stowage (noun)
a room in which things are stored	the act of packing or storing away
	a room in which things are stored
	the charge for stowing goods