cannon cracker vs firecracker

cannon cracker and firecracker both are nouns.

Word	Noun	Adjective	Verb	Adverb
cannon cracker	Yes	No	No	No
firecracker	Yes	No	No	No

As nouns, firecracker is a hypernym of cannon cracker; that is, firecracker is a word with a broader meaning than cannon cracker:

cannon cracker: a large firecracker
firecracker: firework consisting of a small explosive charge and fuse in a heavy paper casing

Other hypernyms of cannon cracker include banger, cracker.

cannon cracker (noun)	firecracker (noun)
a large firecracker	firework consisting of a small explosive charge and fuse in a heavy paper casing