In anatomy, a fossa (/ˈfɒsə/;[1][2] pl.
: fossae (/ˈfɒsiː/ or /ˈfɒsaɪ/); from Latin 'ditch, trench') is a depression or hollow, usually in a bone, such as the hypophyseal fossa (the depression in the sphenoid bone).
[3] Some examples include: In the skull: In the mandible: In the torso: In the upper limb: In the lower limb: