soothsayer vs seer

soothsayer and seer both are nouns.

Word	Noun	Adjective	Verb	Adverb
soothsayer	Yes	No	No	No
seer	Yes	No	No	No

As nouns, seer is a hypernym of soothsayer; that is, seer is a word with a broader meaning than soothsayer:

soothsayer: someone who makes predictions of the future (usually on the basis of special knowledge)
seer: a person with unusual powers of foresight

Other hypernyms of soothsayer include illusionist, visionary.

soothsayer (noun)	seer (noun)
someone who makes predictions of the future (usually on the basis of special knowledge)	a person with unusual powers of foresight
	an authoritative person who divines the future
	an observer who perceives visually