account payable vs indebtedness

account payable and indebtedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
account payable	Yes	No	No	No
indebtedness	Yes	No	No	No

As nouns, indebtedness is a hypernym of account payable; that is, indebtedness is a word with a broader meaning than account payable:

account payable: a liability account showing how much is owed for goods and services purchased on credit
indebtedness: an obligation to pay money to another party

Other hypernyms of account payable include financial obligation, liability.

account payable (noun)	indebtedness (noun)
a liability account showing how much is owed for goods and services purchased on credit	a personal relation in which one is indebted for a service or favor
	an obligation to pay money to another party