The most well-known nickname of President Andrew Jackson was "Old Hickory." This nickname was given to him by his soldiers due to his toughness and determination, likening him to the hard, strong wood of the hickory tree. Additionally, the Creek Nation called him "Sharp Knife" for his aggressive fighting tactics. Other nicknames include "The Hero of New Orleans," "King Andrew," "Mad Dog Jackson," and "People's President," among others. But "Old Hickory" remains the most iconic and widely recognized nickname for Andrew Jackson.