Answer
It is easy to remember that abduction and adduction mean movements in opposite directions with respect to a midline or medial axis. The meaning of "add" is elementary knowledge to everyone who has been to school. Adding "A' to "T" for instance, means to bring "A" toward "T" or closer to "T". Similarly, if we think of adding an upper limb (lateral structure) to the trunk (midline structure), it can only mean moving the lateral structure, the limb medially, or closer to the midline structure, the trunk. If this device serves to remind us of the meaning of ad-duction then the rest is simple. All that is necessary is to remember that ab-duction is the opposite movement to ad-duction. This solves the memory problem of distinguishing the meaning of "adduction" from the meaning of 'abduction'.
Work Step by Step
Adduction is the movement of a body part towards the midline in a given plane. The movement of that body part in the opposite direction in the same plane--away from the midline is abduction. These terms are easily confused because they have similar sounds when pronounced indistinctly. But if one remembers that "ad" means "to add" as in addition; that is to "move towards" or "join with", or "move closer " to something; then if one thinks of the object to be moved as an upper limb and the linear destination as the trunk (midline), then the adduction of an upper limb in the coronal plane can specify only one movement, that is movement of the limb closer to the trunk. Since it is clear to everyone, that abduction is the opposite action of adduction, this easily remembered illustration is an effective learning device .
