Final answer:
The medical term that means 'toward the midline of the body' is medial, which describes a position closer to the center of the body.
Step-by-step explanation:
The medical term meaning 'toward the midline of the body' is medial. This term is used to describe the position of something that is closer to the center (midline) of the body compared to another part. For example, the hallux (big toe) is the medial toe as it is closer to the midline than the other toes. The options provided in the question such as lateral, ventral, and dorsal, describe other directions: lateral being towards the side of the body, ventral referring to the front or anterior aspect, and dorsal indicating the back or posterior aspect of the body.