building vs fabrication

building and fabrication both are nouns.

Word	Noun	Adjective	Verb	Adverb
building	Yes	No	No	No
fabrication	Yes	No	No	No

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

building (noun)	fabrication (noun)
the act of constructing something	the act of making something (a product) from raw materials
the commercial activity involved in repairing old structures or constructing new ones	the act of constructing something (as a piece of machinery)
a structure that has a roof and walls and stands more or less permanently in one place	writing in a fictional form
the occupants of a building	the deliberate act of deviating from the truth
	a deliberately false or improbable account