Assuming "kanban" is the Japanese 看板[1] ("kanban", billboard), the Department of Redundancy Department would like a word with you and Kanboard regarding "kanban board".
Incorrect assumption. This "kanban" refers to the signalling process you can use to maintain even levels of buffer inventory in processes that are too variable to do prodution levelling.
A board is just one implementation of this signalling process, but by no way implied by it.
[1]: https://jisho.org/search/%E7%9C%8B%E6%9D%BF