fossa for lacrimal sac fossa for lacrimal sac a smooth, more deeply concave depression on the lacrimal bone, which forms the medial wall of the orbital cavity, in which the lacrimal sac that drains into the nasolacrimal duct is located, is referred to as the lacrimal fossa (or fossa for the lacrimal sac). fossa for lacrimal saclacrimal fossa for the lacrimal saclacrimal bone, medial anterior orbital cavity. the location of the lacrimal fossa for the lacrimal sacdetailsidentifierslatinfossa sacci lacrimalista98a02.1.00.082ta2486fma54390anatomical terms of bone