coach's name-use license
In sumo, a license that allows a retired wrestler to use a stablemaster's name and run a stable. Rare outside sumo context.
To obtain a coach's name-use license, one must pass a strict screening by the Japan Sumo Association.
Compound of 親方 (oyakata, 'stablemaster') and 株 (kabu, 'stock' or 'license'). The exact historical derivation is uncertain, but the term reflects the sumo world's practice of treating stablemaster names as transferable rights.