post office vs subdivision

post office and subdivision both are nouns.

Word	Noun	Adjective	Verb	Adverb
post office	Yes	No	No	No
subdivision	Yes	No	No	No

As nouns, subdivision is a hypernym of post office; that is, subdivision is a word with a broader meaning than post office:

Other hypernyms of post office include arm, branch.

post office (noun)	subdivision (noun)
a children's game in which kisses are exchanged for pretended letters	the act of subdividing; division of something previously divided
a local branch where postal services are available	a section of a section; a part of a part; i.e., a part of something already divided
	a self-contained part of a larger composition (written or musical)
	a division of some larger or more complex organization
	an area composed of subdivided lots