Final answer:
The term "hand" when describing an end mill refers to the direction of rotation of the end mill. The hand of an end mill determines the direction in which the flutes spiral along the length of the tool.
Step-by-step explanation:
The term "hand" when describing an end mill refers to the direction of rotation of the end mill. The hand of an end mill determines the direction in which the flutes spiral along the length of the tool. There are two possible hands: right-hand (clockwise) and left-hand (counterclockwise). The hand of the end mill affects the cutting action and chip removal during milling operations.