n. The geological study of the Earth's structure and composition.
the GNU version of the Collaborative International Dictionary of English
n. That part of geology which treats of the materials of the earth's structure, and its general exterior and interior constitution.
The Century Dictionary and Cyclopedia
n. Literally, knowledge of the earth: a geological term variously used.
Word Usage
"As professor at Freiberg beginning in 1775, after, rather than before Guettard's work, he trained the students who, returning to their own countries, spread the new science which he called "geognosy" but they called "Wernerism" and "Neptunism.""