 The Navy will frock more than 18,000 sailors during this advancement cycle. The early use of the word frock referred to the long cloak worn by monks in which to frock meant to invest with priestly office or privilege. Another explanation for the term frock is for the ornamental closure on the coat called a frog. The expression could have evolved from frog coat to frock coat. The practice of frocking in the Navy dates back as early as 1802 when personnel wore the uniform of the next highest rank to assume the duties and responsibilities of that rank prior to their actual promotion. There's no definite point at which the practice was first established but what remains constant is the Navy's commitment to investing in effective leaders in the fleet. From the Defense Media Activity, I'm Petty Officer Jen Blake.