speculation

Reasoning based on inconclusive evidence; conjecture or supposition.

A conclusion, opinion, or theory reached by conjecture.

Contemplation or consideration of a subject; meditation.

Engagement in risky business transactions on the chance of quick or considerable profit.

A commercial or financial transaction involving speculation.

The act or state of speculating, or of seeing or looking; intelligent contemplation or observation; a viewing; inspection.

The pursuit of truth by means of thinking, especially mathematical reasoning and logical analysis; meditation; deep and thorough consideration of a theoretical question.

In philosophy, sometimes, a purely a priori method of philosophizing: but commonly in philosophy the word has the meaning 2, above.