There isn't a widely accepted international standard for a "nautical league." The nautical mile (nmi) is the more common and internationally recognized unit of measurement for distances at sea. A nautical mile is approximately equal to one minute of latitude along a meridian, and it is used worldwide for maritime and aviation navigation.
In some regions, historical or localized variations of the league may have been used in the past, but these are not part of the modern international system of measurement. It's important to note that such variations can differ by country and even within different historical periods.
For precise and internationally recognized measurements in maritime and aviation contexts, the nautical mile is the preferred unit of distance. One nautical mile is equal to approximately 1.852 kilometers or 1.15078 statute miles (land miles).
A "fermi" (symbol: fm) is a unit of length used in physics to describe extremely small distances at the atomic and subatomic scale. One fermi is equal to 10^-15 meters or 0.000000000000001 meters. It is named after the Italian physicist Enrico Fermi, who made significant contributions to nuclear physics and particle physics.
The fermi is particularly useful for describing the sizes of atomic nuclei and the distances between particles within atomic nuclei. For example, the typical diameter of an atomic nucleus is on the order of a few femtometers (1 femtometer = 1 fm). It is also used in high-energy particle physics to describe the cross-sectional area of particle interactions.
In summary, the fermi is an essential unit of length for understanding the microscopic world of atoms, nuclei, and subatomic particles, where distances are incredibly small.