JESTER, a provider of " jests " or amusements, a buffoon, especially a professional fool at a royal court or in a nobleman's household (see FOOL). The word " jest," from which " jester " is formed, is used from the 16th century for the earlier " gest," Lat. gesta, or res gestae, things done, from gerere, to do, hence deeds, exploits, especially as told in history, and so used of the metrical and prose romances and chronicles of the middle ages. The word became applied to satirical writings and to any longwinded empty tale, and thence to a joke or piece of fun, the current meaning of the word.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)