perceptible by the senses especially the sense of touch; "skin with a tangible roughness"
(of especially business assets) having physical substance and intrinsic monetary value ; "tangible property like real estate"; "tangible assets such as machinery"
based on custom rather than documentation; "an unwritten law"; "rites...so ancient that they well might have had their unwritten origins in Aurignacian times"- J.L.T.C.Spence