sciatic notch

noun

: either of two notches on the dorsal border of the hip bone on each side that when closed off by ligaments form the corresponding sciatic foramina:

a

: a relatively large notch just above the ischial spine that is converted into the greater sciatic foramen by the sacrospinous ligament

called also greater sciatic notch

b

: a smaller notch just below the ischial spine that is converted to the lesser sciatic foramen by the sacrospinous ligament and the sacrotuberous ligament

called also lesser sciatic notch