Indefinite ranking is a type of ranking system that does not assign a specific numerical value to each item being ranked. Instead, it assigns a relative value to each item, such as 'HIGH', 'MEDIUM', or 'LOW'. This type of ranking system is often used when there is no clear consensus on the exact numerical value of an item, or when the items being ranked are subjective in nature. The term 'NTH' is an abbreviation for 'NTH degree', which is a phrase used to describe something that is of the highest quality or importance.