venture vs surmise

venture and surmise both are nouns.

Word	Noun	Adjective	Verb	Adverb
venture	Yes	No	Yes	No
surmise	Yes	No	Yes	No

As verbs, surmise is a hyponym of venture; that is, surmise is a word with a more specific, narrower meaning than venture:

Other hyponyms of venture include anticipate, call, forebode, foretell, predict, prognosticate, promise, suspect.

venture (noun)	surmise (noun)
any venturesome undertaking especially one with an uncertain outcome	a message expressing an opinion based on incomplete evidence
a commercial undertaking that risks a loss but promises a profit
an investment that is very risky but could yield great profits

venture (verb)	surmise (verb)
put forward, of a guess, in spite of possible refutation	infer from incomplete evidence
put at risk	imagine to be the case or true or probable
proceed somewhere despite the risk of possible dangers