What does the prefix "ad-" indicate?

The prefix "ad-" is derived from Latin, where it signifies movement or directionality toward something. In medical terminology, this prefix is commonly used to indicate an approach towards a structure or an increase in some manner. For example, in the term "adduction," it refers to the movement of a limb toward the midline of the body. This understanding of "ad-" as "toward" helps clarify how it modifies the meaning of various terms in veterinary science and medicine.