bag, wrap

包 is composed of 勹(bag, wrap) and 巳(sixth earthly branch). 勹 is the picture of a fetal membrane, while 巳 is the picture of a fetus, so 包 depicts a fetus being wrapped inside the fetal membrane. The original meaning of 包 is fetal membrane, but such meaning has been replaced by 胞, now 包 only means bag or wrap.