conjecture

A statement or an idea which is unproven, but is thought to be true; a guess.

I explained it, but it is pure conjecture whether he understood, or not.

A supposition based upon incomplete evidence; a hypothesis.

The physicist used his conjecture about subatomic particles to design an experiment.

A statement likely to be true based on available evidence, but which has not been formally proven.

Interpretation of signs and omens.

To guess; to venture an unproven idea.

I do not know if it is true; I am simply conjecturing here.

What could have been done by such a machine downhill can only be conjectured, for the maximum speed was restricted rigidly to 80 m.p.h.

To infer on slight evidence; to guess at.

February 22, 1685, Robert South, All Contingences under the Direction of God's Providence (sermon preached at Westminster Abbey)

"Most likely he who is the shorter of the two;—no! he goes in the first, and is, of course, the eldest; but we have no time for conjecturing now." Human reason can then, at the best, but conjecture what will be.