History: Samurai Portrait

The radical shi (士) on the other hand seems to have originally meant a person who performs some function or who has the ability in some field. Early in Chinese history it came to define the upper class of society, and in the Book of Han this definition is given :
The shi, the farmer, the craftsman, and the tradesman are the four professions of the people. He who occupies his rank by means of learning is called a shi.
Wilson states that the shi, as the highest of the four classes, brandished the weapons as well as the books. bushi therefore translates as "a man who has the ability to keep the peace, either by literary or military means, but predominantly by the latter".
It was not until the early modern period, namely the Azuchi-Momoyama period and early Edo period of the late 16th and early 17th centuries that the word saburai was replaced with samurai. However, the meaning had changed long before that.