early 15c., "ligament in the neck," from Latin cervix "the neck, nape of the neck," from PIE *kerw-o-, from root *ker- (1) "horn, head" (see horn (n.)). Applied to various neck-like structures of the body, especially that of the uterus (by 1702), where it is shortened from medical Latin cervix uteri (17c.). Sometimes in medical writing 18c.-19c. cervix of the uterus to distinguish it from the neck sense.
