midline
mid line |ˈmidˌlīn ˈmɪdlaɪn | ▶noun [ often as modifier ] a median line or plane of bilateral symmetry, esp. that of the body: the abdomen was opened by a midline incision.
mid |line |ˈmɪdlʌɪn | ▶noun [ often as modifier ] a median line or plane of bilateral symmetry, especially that of the body: the abdomen was opened by midline incision.