Final answer:
The term for moving the tooth back and forth within the socket is Luxation, which is the dislodgement of a tooth from its normal position in the bone.
Step-by-step explanation:
The term that means to move the tooth back and forth within the socket is D) Luxation. This term refers to an injury where the tooth has been dislodged from its normal position in the bone.
Luxation can vary in severity from a slight loosening of the tooth (subluxation) to a complete displacement. It is important to note that while terms like excursion are related to the movement of the jaw or mandible side to side, luxation specifically points to the abnormal movement or displacement of a tooth within its socket.
A gomphosis is the peg-and-socket joint that holds a tooth securely in place within the jawbone, and this type of joint is usually not mobile under normal conditions.