conjecture vs formulate

conjecture is a noun but formulate is not a noun.

Word	Noun	Adjective	Verb	Adverb
conjecture	Yes	No	Yes	No
formulate	No	No	Yes	No

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

Other hyponyms of conjecture include construct, reconstruct, retrace, develop, explicate.

conjecture (noun)	formulate (noun)
a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence)
reasoning that involves the formation of conclusions from incomplete evidence
a message expressing an opinion based on incomplete evidence

conjecture (verb)	formulate (verb)
to believe especially on uncertain or tentative grounds	put into words or an expression
	elaborate, as of theories and hypotheses
	come up with (an idea, plan, explanation, theory, or principle) after a mental effort
	prepare according to a formula