truest
adjective
Definitions
(of a statement) Conforming to the actual state of reality or fact; factually correct.
Example: This is a true story.
Conforming to a rule or pattern; exact; accurate.
Example: a true copy; a true likeness of the original
Of the state in Boolean logic that indicates an affirmative or positive result.
Example: "A and B" is true if and only if "A" is true and "B" is true.
Loyal, faithful.
Example: He’s turned out to be a true friend.