1 the science of the earth, including the composition, structure, and origin of its rocks.
2 this science applied to any other planet or celestial body.
3 the geological features of a district.
Derivatives:
geologic adj. geological adj. geologically adv. geologist n. geologize v.tr. & intr. (also -ise).
Etymology: mod.L geologia (as GEO-, -LOGY)
Useful english dictionary. 2012.