Possibility

The quality or state of being possible; the power of happening, being, or existing.

That which is possible; a contingency; a thing or event that may not happen; a contingent interest, as in real or personal estate.

a possible alternative; "bankruptcy is always a possibility"

a tentative insight into the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena; "a scientific hypothesis that survives experimental testing becomes a scientific theory"; "he proposed a fresh theory of alkalis that later was accepted in chemical practices"