the.com/cervix

means The narrow, lower part of the uterus that connects it to the vagina, acting as a gateway that stays shut most of the time and opens for menstruation, childbirth, or related medical reasons.

from From Latin cervix, meaning 'neck' — the same word Romans used for the neck atop your shoulders. Anatomists borrowed it because the structure sits like a narrow neck joining the body (the uterus) to what lies below, the same logic behind 'neck of the womb,' an older English phrase for the same part. The root is ancient and its further deep origins are uncertain, but the 'neck' sense is the solid, attested throughline.