It's a stylized lily flower that has been used as a heraldic symbol for centuries, most famously as the emblem of the French monarchy.
Here are some additional points about the fleur-de-lis:
* Not a true lily: The design is not based on a specific lily species, but rather a stylized version with three petals.
* Symbolism: The fleur-de-lis has been associated with purity, innocence, and royalty.
* Usage: It has been used by various institutions and individuals beyond the French monarchy, including the Boy Scouts of America, the University of Notre Dame, and many others.
Let me know if you'd like to learn more about the history or symbolism of the fleur-de-lis!