Definitions for "esq"
a title of respect for a member of the English gentry ranking just below a knight; placed after the name
Esquire. Originally denoted a knight's squire. Later it became appended to the name of individuals who had no official class standing, and therefore no formal title, but who had sufficient social stature to be considered a cut above the rest. In the main it was used for lawyers, but later came to be applied more generally. A remnant of this usage is found in the US legal profession today, where lawyers still use the term when writing to each other.