SikkimPronunciation: /ˈsɪkɪm/Definition of Sikkim a state of NE India, in the eastern Himalayas between Bhutan and Nepal, on the border with Tibet; capital, Gangtok. After British rule it became an Indian protectorate, becoming a state of India in 1975. Derivatives SikkimesePronunciation: /ˌsɪkɪˈmiːz/ adjective & noun Sikkim in other Oxford dictionaries Definition of Sikkim in the US English dictionary