What is to reduce the diameter of (an object) near its end, by making a groove around it; -- used with down; as, to neck down a shaft. v. t. & i. To kiss and caress amorously. n. necking called?

neck — To reduce the diameter of (an object) near its end, by making a groove around it; -- used with down; as, to neck down a shaft. v. t. & i. To kiss and caress amorously. n. necking. (Webster's 1913.)

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