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Chicken neck or chicken's neck can literally refer to the neck of a chicken or figuratively to any narrow stretch of land connecting two larger parts of a state or territory and surrounded by the territory of another territory or state.
Chicken's Neck is the specific name of two separate areas or strips of land in South Asia
Siliguri Corridor, a narrow strip of land which connects the northeastern states to the rest of India
Chicken's Neck (Pakistan), a narrow strip of Pakistani territory that lies south of Akhnoor in Indian Jammu and Kashmir