being in or directed toward the midline or mesial plane of the body
mesial详细解释
me.si.al adj.（形容词）Of, in, near, or toward the middle.中间的、位于正中的、靠近正中的或向正中的Dentistry Situated toward the middle of the front of the jaw along the curve of the dental arch.【牙科学】 朝向齿弓中线的：位置沿齿弓弧线向下巴前部正中的 【引伸】 me.sially adv.（副词）
