The earth conceived of as the female principle of fertility WordNet 3.0 & Open English WordNet

A mother goddess is a major goddess characterized as a mother or progenitor, either as an embodiment of motherhood and fertility or fulfilling the cosmological role of a creator- and/or destroyer-figure, typically associated the Earth, sky, and/or the life-giving bounties thereof in a maternal relation with humanity or other gods. Wikipedia

The personification of the Earth, (chiefly) conceived as a fertile, nurturing, and loving mother. Wiktionary

Personification of Earth. Wiktionary (translation)

A goddess, often portrayed as the Earth Mother, who serves as a general fertility deity, the bountiful embodiment of the earth. Wiktionary

Goddess who serves as a fertility deity. Wiktionary (translation)