Galactic astronomy
Galaxy formation and evolution
Galois geometry
Game design
Game studies
Game theory
Gamma-ray astronomy
Gas mechanics
Gastroenterology
Gastronomy
Gemology
Gender and sexuality studies
Gender archaeology
Gender dysphoria
Gender history
Gender identity
Gender role
Gender studies/Gender theory
Genderqueer
Gene-culture coevolution
General practice
General relativity
General systems theory
General topology
Genetics
Geoarchaeology
Geobiology
Geochemistry
Geodesy
Geodynamics
Geography
Geography
Geology
Geomagnetism
Geometric number theory
Geometric topology
Geometrical optics
Geometry and Topology
Geomorphology
Geophysics
Geopolitics (Political geography)
Geotechnical engineering
Geriatrics
German history
German studies
Gerontology
Ghanaian history
Glaciology
Glyptology
Gnosticism
Goal
Gourmet
Governmental affairs
Grammar
Grand strategy
Graph theory
Graphic arts
Graphic design
Gravitational astronomy
Gravitational wave astronomy
Great ages archaeology
Green chemistry
Green economics
Grid computing
Group psychology
Group theory
Growth economics
Guerrilla warfare
Gynaecology
Gynocentrism