An assumption taken to be true for the purpose of argument or investigation.
Used loosely, a tentative conjecture explaining an observation, phenomenon or scientific problem that can be tested by further observation, investigation and/or experimentation. As a scientific term of art, see the attached quotation. Compare to theory, and quotation given there.
The antecedent of a conditional statement.
The entirety of all that is real.
The real world.
The state of being actual or real; realness.
An individual observer's own subjective perception of that which is real.
A real entity, event, or other fact.