Epigeal, epigean, epigeic and epigeous are biological terms describing an organism's activity above the soil surface.
In botany, a seed is described as epigeal when the cotyledons of the germinating seed expand, throw off the seed shell and become photosynthetic above the ground. The opposite kind, where the cotyledons remain non-photosynthetic, inside the seed shell, and below ground, is hypogeal.
An organism is epigean, epigeic or epigeous if it crawls (epigean), creeps like a vine (epigeal), or grows (epigeous) on the soil surface, or more generally in animals, neither burrows nor swims nor flies. Consequently, the opposite term depends on the circumstances. It can be fossorial (burrowing), troglobitic - or stygobitic, hypogean etc. - (for cave-living organisms), or hypogeic and hypogeous (for plants and fungi that grow underground).