note payable vs promissory note

note payable and promissory note both are nouns.

Word	Noun	Adjective	Verb	Adverb
note payable	Yes	No	No	No
promissory note	Yes	No	No	No

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

note payable: a note promising to pay a certain amount of money at a certain time
promissory note: a promise to pay a specified amount on demand or at a certain time

Other hypernyms of note payable include note, note of hand.

note payable (noun)	promissory note (noun)
a note promising to pay a certain amount of money at a certain time	a promise to pay a specified amount on demand or at a certain time