Che refers to the diagonal pattern of the "three" pip on the tile. Deng refers to the "one" pip on the tile.
See also: Tien Gow, Pai Gow, Gwat Pai
... Ongar tube station[?] St Mary's (Whitechapel Road) tube station[?] South Acton tube station[?] South Kentish Town tube station[?] Swiss Cottage (Metropolitan Line) ...