cubbyhole vs compartment

cubbyhole and compartment both are nouns.

Word	Noun	Adjective	Verb	Adverb
cubbyhole	Yes	No	No	No
compartment	Yes	No	No	No

As nouns, compartment is a hypernym of cubbyhole; that is, compartment is a word with a broader meaning than cubbyhole:

cubbyhole (noun)	compartment (noun)
a small compartment	a partitioned section, chamber, or separate room within a larger enclosed area
a small secluded room	a space into which an area is subdivided