mesio-

A midline.

Formed irregularly from Greek mesos, middle.

The adjective mesial refers to a direction or position towards the middle line of a body. Compounds of mesio‑ appear mainly in dentistry: mesiobuccal (Latin bucca, cheek), between the mesial and buccal surfaces of a tooth, or mesiodens (Latin dens, dent‑, tooth), an extra tooth that develops in the midline of the palate, between the central incisors.