Hypogaeic \Hyp`o*g[ae]"ic\, a. [Pref. hypo- + Gr. gai^a, gh^, earth.] (Chem.) Pertaining to, or obtained from, the peanut, or earthnut ({Arachis hypog[ae]a}). {Hypog[ae]ic acid} (Chem.), an acid in the oil of the earthnut, in which it exists as a glyceride, and from which it is extracted as a white, crystalline substance.