Pertaining to or based on experience (often, in contrast with having a basis in theoretical explanation).
Pertaining to, derived from, or testable by observations made using the physical senses or using instruments which extend the senses.
Verifiable by means of scientific experimentation.
Characterized by speculation; based on guessing, unfounded opinions, or extrapolation.
Pursued as a gamble, with possible large profits or losses; risky.
Pertaining to financial speculation; Involving or resulting from high-risk investments or trade.