What is the term for the line that divides the hair at the scalp?

The term that defines the line dividing the hair at the scalp is "part." A part is crucial in hairstyling as it determines how the hair is styled and can influence the overall appearance of a hairstyle. Different types of parts can create various looks, such as a middle part, side part, or zigzag part, and each type can highlight different facial features or balance the overall shape of the head.

In comparison, a "section" generally refers to a subsection of hair that is taken for cutting, styling, or treatment purposes, while a "layer" describes a technique where hair is cut to different lengths to create texture and volume. "Curve" is more often associated with the shape of the hairstyle rather than dividing hair at the scalp. Thus, recognizing a part is essential for achieving the desired styling outcome.