debt vs indebtedness

debt and indebtedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
debt	Yes	No	No	No
indebtedness	Yes	No	No	No

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

Other hypernyms of debt include financial obligation, liability.

debt (noun)	indebtedness (noun)
an obligation to pay or do something	a personal relation in which one is indebted for a service or favor
money or goods or services owed by one person to another	an obligation to pay money to another party
the state of owing something (especially money)