practical, established, tested, validated, confirmed, distinct, empiric, factual, empirical, concrete, time-tested, actual, attested, clinical, definite, nontheoretical, proven, verified, authenticated, observational, demonstrated, real, defined, nonspeculative, substantiated.
Usage examples :
1) This might do: 'In Assignation's name he assignats'; signifying that he pre- eminently flourishes hypothetical promises, to pay by appointment. - "The Complete Project Gutenberg Works of George Meredith", George Meredith.
3) " He who will determine," returned Imlac, " against that which he knows because there may be something which he knows not; he that can set hypothetical possibility against acknowledged certainty, is not to be admitted among reasonable beings. - "Rasselas, Prince of Abyssinia", Samuel Johnson.