From BiblePortal Wikipedia

King James Dictionary [1]


1. A fixed or real state truth fact.

Know for a certainty, that the Lord your God will no more drive out these nations.  Joshua 23 .  Luke 1 .

2. Full assurance of mind exemption from doubt.

Certainty is the perception of the agreement or disagreement of our ideas.

3. Exemption from failure as the certainty of an event, or of the success of a medicine.

The certainty of punishment is the truest security against crimes.

4. Regularity settled state.

Webster's Dictionary [2]

(1): (n.) Clearness; freedom from ambiguity; lucidity.

(2): (n.) The quality, state, or condition, of being certain.

(3): (n.) A fact or truth unquestionable established.

Hastings' Dictionary of the New Testament [3]

See Assurance.