1) genuine; known to be true (authentic)

2) a statement that must be true because an earlier and related statement is true (corollary)

3) to need; rely (on the support etc of a person, thing) in order to exist, to be true or to succeed (depend)

4) something that has happened or been done; something known to be true or able to be proved (fact)

5) what one has heard another person or other people say but does not know to be true (hearsay)

6) not likely to be true or to happen (improbable)

7) to suppose (something) to be true (presume)

8) to supply proof of (something); show (something) beyond doubt to be true (prove)

9) the act of supposing something to be true but without proof; a guess (supposition)

10) a statement with logical or mathematical reasoning shows to be true (theorem)