hypothesize vs speculate

hypothesize and speculate both are verbs.

Word	Noun	Adjective	Verb	Adverb
hypothesize	No	No	Yes	No
speculate	No	No	Yes	No

As verbs, hypothesize and speculate are synonyms defined as:

hypothesize and speculate: to believe especially on uncertain or tentative grounds

Other synonyms of hypothesize include conjecture, hypothecate, hypothesise, suppose, theorise, theorize.

hypothesize (verb)	speculate (verb)
to believe especially on uncertain or tentative grounds	reflect deeply on a subject
	to believe especially on uncertain or tentative grounds
	talk over conjecturally, or review in an idle or casual way and with an element of doubt or without sufficient reason to reach a conclusion
	invest at a risk