\E*phip"pi*um\, n. [L., saddle cloth, fr. Gr. ?; 'epi`
on + ? horse.]
1. (Anat.) A depression in the sphenoid bone; the pituitary
   fossa.
2. (Zo["o]l.) A saddle-shaped cavity to contain the winter
   eggs, situated on the back of Cladocera.