King James Bible

CONVERSATION, noun

1. General course of manners; behavior; deportment; especially as it respects morals.

Let your conversation be as becometh the gospel. Philippians 1:27.

Be ye holy in all manner of conversation 1 Peter 1:15.

2. A keeping company; familiar intercourse; intimate fellowship or association; commerce in social life. Knowledge of men and manners is best acquired by conversation with the best company.

3. Intimate and familiar acquaintance; as a conversation with books, or other object.

4. Familiar discourse; general intercourse of sentiments; chat; unrestrained talk; opposed to a formal conference.

What I mentioned in conversation was not a new thought.

[This is now the most general use of the word.]