What is "kudan"

Kudan may refer to one of these:

• Kudan, Rajasthan, in India
• Kudan, Nigeria, a Local Government Area in Kaduna State
• Kudan 9th degree black belt, Also spelt Kyudan
• Kudan Augmented Reality, an Augmented Reality Technology company based in the UK
• The Kudan , a residence in Tokyo, Japan, since 1944 the official residence of the Philippine Ambassador to Japan
• Kudan (yōkai), a Japanese spirit

The is a yōkai which became widely known throughout Japan during the first half of the 19th century.