ESQUIRE

In the Middle Ages, the original esquires were aspirants for knighthood, entourage and shield-bearers for the knights. The expression came into English at the time of the Norman Conquest, via the Old French esquier from the Latin scutarius (shield-bearer).

The word esq. was later quite frequently used to be a sign that the individual addressed was of social rank somewhat more prominent than that of trades people, who were called plainly Mr.

Now, in America at least, Esq. is used predominantly as a courtesy title when addressing correspondence to attorneys. One, on no account, by the way, uses Mr. and Esq. in the same acknowledgment.