THESAURUS
firsthand
absolute, adducible, admissible, attestative, attestive, authentic, avant-garde, based on, callow, certain, circumstantial, conclusive, convincing, creative, cumulative, damning, decisive, determinative, dewy, documentary, documented, ever-new, evergreen, evidential, evidentiary, ex parte, eye-witness, factual, final, fledgling, founded on, fresh, green, grounded on, hearsay, imaginative, immature, immediate, implicit, incontrovertible, indicative, indisputable, intact, irrefutable, irresistible, maiden, maidenly, material, neoteric, nestling, new, novel, nuncupative, original, overwhelming, presumptive, primary, pristine, probative, raw, reliable, revolutionary, sempervirent, significant, suggestive, sure, symptomatic, telling, unbeaten, underived, undeveloped, unfledged, unhandled, unique, untouched, untried, untrodden, unused, valid, vernal, virgin, virginal, weighty, young