In the context of anatomy and physiology, opposition is the movement that involves bringing the thumb and a finger (usually the little or index finger) together. This action allows for gripping and manipulating objects of various sizes.
Related terms
Flexion: The bending movement around a joint in a limb that decreases the angle between the bones of that limb.
Extension: The straightening movement that increases the angle between body parts, such as straightening an arm or leg.
Abduction: The movement of a limb away from the midline or center line of the body