A gynecological instrument for delineating the fornix of the vagina during laparoscopic operations having a solid ring with a guiding groove for easy and safe opening of the vagina laparoscopically. The solid ring has a protrusion outward which pushes the vaginal wall toward the peritoneal cavity, creating a bulging of the vaginal wall, making it easily identifiable. The solid ring is permanently attached to the proximal end of the base by a semi-cylindrical wall which creates a window anteriorly, for better visualization of the cervix and easy insertion of a cannula or delineator into the uterine cavity. The vaginal delineator is locked to the head of the uterine mobilizer by inserting the locking end of a cannula, delineator or vaginal delineator lock, through the hole of the delineator and into the head of the uterine mobilizer. An elastic diaphragm is provided with different sizes for obstruction of the vagina, which does not allow flow in any direction. This instrument can be used to mobilize the uterus, to inject dye into the uterus and Fallopian tubes, and to delineate the fornix of the vagina, even when the uterus Has been previously removed.