besieger vs petitioner

besieger and petitioner both are nouns.

Word	Noun	Adjective	Verb	Adverb
besieger	Yes	No	No	No
petitioner	Yes	No	No	No

As nouns, petitioner is a hypernym of besieger; that is, petitioner is a word with a broader meaning than besieger:

Other hypernyms of besieger include requester, suppliant, supplicant.

besieger (noun)	petitioner (noun)
an enemy who lays siege to your position	one praying humbly for something
an energetic petitioner	someone who petitions a court for redress of a grievance or recovery of a right