cervical dilation

cervical dilation /dil′ā″shən/ [L, dilatare, to widen] , the diameter of the opening of the cervix in labor as measured on vaginal examination. It is expressed in centimeters or finger breadths; one finger breadth is approximately 2 cm. At full dilation the diameter of the cervical opening is 10 cm.

Cervical dilation (McKinney et al, 2009)