Three of the following words are alike in some manner and hence form a group. Which word does NOT belong to that group? (The words must be considered as meaningful English words and must not be grouped based on the number of letters/number of consonants/vowels in the word).

Jharkhand, Gujarat, and West Bengal are states that border Bangladesh or have coastal boundaries with significant populations, while Sikkim is a landlocked state in the Himalayas. More precisely, Jharkhand, Gujarat, and West Bengal are states that were carved from or border other major states differently — Sikkim is the only one that is a former kingdom that merged with India, making it the odd one out.