That can be deducted, especially with respect to income taxes:
Named but not known or previously mentioned:
Serving to put an end to doubt, question, or uncertainty; decisive:
Find another word for provable. In this page you can discover 9 synonyms, antonyms, idiomatic expressions, and related words for provable, like: in-evidence, inferable, demonstrable, deductible, testable, certain, conclusive, falsifiable and refutable.