Geologist

The origin of the word geologist could be said to be as old as the rocks themselves! While the origin of the word is unknown, some suggest that it may be found in Dorian, an ancient (i.e., 5,000 – 6,000 years or more ago) pre-Indo-European language of Greece. The Dorian word ga (earth) is presumed to be the source of the Greek word gaia (earth, not heaven; land, not sea; a land, country, soil).
 
In Greek mythology, Gaia was a goddess (‘Mother Earth’), the spouse of Uranus and the mother of the Titans.
 
The word-forming element geo- (earth, the Earth) comes from Gaia. Geo forms part of numerous words—geode, geodesic, geography, geometry, George (geo [earth] + ergon [work] = earth worker or, farmer), geophysics, and so on. The word-forming element -logy means discourse, doctrine, theory, science. In brief, geo + logy (Latin geologia) = the study of the earth.
 
The word geology (the science of the past and present condition of the Earth’s crust) came to English in 1795 from Latin geologia. Charles Darwin used the word geologize as a verb.
 
The word geologist is also from 1795. Other forms of the word geologist were geologer (1822) and geologian (1837); however, these words have not survived in common use.
 
Reference: Online Etymological Dictionary, https://www.etymonline.com/
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