Theorise
Part of speech: verb
Definition: To formulate a theory, especially about some specific subject.
Conjecture
Part of speech: noun
Definition: A statement or an idea which is unproven, but is thought to be true; a guess.A supposition based upon incomplete evidence; a hypothesis.A statement likely to be true based on available evidence, but which has not been formally proven.The interpretation of signs and omens.
Part of speech: verb
Definition: To guess; to venture an unproven idea.
Example sentence: If a man dreams that he has committed a sin before which the sun hid his face, it is often safe to conjecture that, in sheer forgetfulness, he wore a red tie, or brown boots with evening dress.