n. In anatomy and zoology, the neck, in the most general sense; the whole neck.n. The necklike prolongation of some flask-shaped infusorians, or of the choanocytes of sponges, which ends in the flagellum and is surrounded by the collar.n. In entomology, the upper part or collar of the prothorax of a beetle, usually called the pronotum.n. In botany: Same as collar, 2 .n. In mosses, the neck or tapering base of the capsule.