Bone / hitbox selection
Also called: Hitbox, Aim bone
Which part of the body the aimbot aims at: head, neck, chest or the closest bone to your crosshair.
Bone selection (or hitbox selection) decides where on an enemy's body the aimbot aims. Common choices are head, neck, chest and closest (whichever bone is nearest your crosshair).
Head-only gives the most damage but also a headshot rate no real player has, which stands out in kill cams and stats. Chest or closest looks far more natural and still wins most fights.
Related: multipoint checks several bones and picks the best visible one.