I. ˈme]zēəl, ˈmē], ]sē-; ˈmēzhəl, -ēsh- adjective
also mesal ]zəl, ]səl
Etymology: mes- + -ial or -al
1. : middle , median
the mesial aspect of the metacarpal head
2. : lying in, being in the region of, or directed toward the mesial plane
the heart is mesial to the lungs
— opposed to distal
• mesi·al·ly -əlē also mesal·ly -əlē adverb
II. adjective
: of, relating to, or being the surface of a tooth that is next to the tooth in front of it or that is closest to the middle of the front of the jaw — compare distal herein proximal herein
• me·si·al·ly -ə-lē\ adverb