position paper vs memo

position paper and memo both are nouns.

Word	Noun	Adjective	Verb	Adverb
position paper	Yes	No	No	No
memo	Yes	No	No	No

As nouns, memo is a hypernym of position paper; that is, memo is a word with a broader meaning than position paper:

position paper: a memorandum summarizing the items of an agreement (used especially in diplomatic communications)
memo: a written proposal or reminder

Other hypernyms of position paper include memoranda, memorandum.

position paper (noun)	memo (noun)
a report that explains or justifies or recommends some particular policy	a written proposal or reminder
a memorandum summarizing the items of an agreement (used especially in diplomatic communications)