Dorsal and ventral
Anatomical reference terms may be confusing because they are different for pigs that walk on four legs vs. upright, bipedal humans.
Toward the back (not rear): for the pig, dorsal is used; for humans, posterior may also be used.
Toward the front/belly: for the pig, ventral is used; for humans, anterior may also be used.
Virtual Fetal Pig Dissection