relation of the palatomaxillary width, measured between the outer borders of the alveolar arch just above the middle of the second molar tooth, and the palatomaxillary length, measured from the alveolar point to the middle of a transverse line touching the posterior borders of the two maxillae: (palatomaxillary width × 100)/palatomaxillary length; it notes the varying forms of the dental arcade and palate. SYN: palatal index, palatine index.