The index finger (also referred to as forefinger, first finger, second finger, pointer finger, trigger finger, digitus secundus, digitus II, and many other terms) is the second digit of a human hand. It is located between the thumb and the middle finger. It is usually the most dextrous and sensitive digit of the hand, though not the longest. It is shorter than the middle finger, and may be shorter or longer than the ring finger (see digit ratio).
HINT:
Forefinger in the context of Sling (weapon)
A sling is a projectile weapon typically used to hand-throw a blunt projectile such as a stone, clay, or lead "sling-bullet". It is also known as the shepherd's sling or slingshot (in British English, although elsewhere it means something else). Someone who specializes in using slings is called a slinger.
A sling has a small cradle or pouch in the middle of two retention cords, where a projectile is placed. There is a loop on the end of one side of the retention cords. Depending on the design of the sling, either the middle finger or the wrist is placed through a loop on the end of one cord, and a tab at the end of the other cord is placed between the thumb and forefinger. The sling is swung in an arc, and the tab released at a precise moment. This action releases the projectile to fly inertially and ballistically towards the target. By its double-pendulum kinetics, the sling enables stones (or spears) to be thrown much further than they could be by hand alone.
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