‘Grandmaster’ is the title given to the highest levels of black belt in Taekwondo. A grandmaster is senior to a master. Typically, the title of ‘grandmaster’ is reserved for ninth degree black belt practitioners in Taekwondo.
If an organisation also awards tenth degree black belts (which is not a universal convention), they will also be called grandmasters.
There can be more than one grandmaster within an organisation, and while they are often involved in leading the administration of the organisation, this is not always the case. Smaller organisations may not have any grandmasters within them, as it takes on the order of decades to reach this level.
Get some Taekwondo merch!
Want to learn more?
If you'd like to learn more about the Korean terminology used in Taekwondo, consider buying this book: Taekwondo Terminology. It contains an extensive dictionary of terms used in Taekwondo, as well as explanations on how to pronounce Korean words, and aspects of Korean grammar.