G M (or GM, Geiger-Muller) Counter or Tube

GAAP (General Accepted Accounting Principles)

Gadolinium (Gd)

Gage R&R (Repeatability and Reproducibility)

Galaxy

Gale

Gallium (Ga)

Gallium Arsenide (GaAs)

Gallon (gal)

Galvanic Anode

Galvanic Cell 

Galvanic Corrosion

Galvanic Couple

Galvanic Current

Galvanic Series

Galvanised Coating or Galvanisation

Galvanising

Galvano Dynamic

Galvanostatic

Game

Game Theory

Gamma (γ) Radiation

Gamma (γ) Ray

Gantry Crane

Gantt Chart

Gap

Gap Analysis

Gas

Gas and Electricity Markets Authority (GEMA)

Gas Cap (Cap Gas)

Gas Coke

Gas Condensate

Gas Condensate Ratio

Gas Constant (R)

Gas Cycling or Re-Cycling

Gas Detector 

Gas Enrichment

Gas Gathering System

Gas Generator

Gas Gravity

Gas Grid or Network

Gas Hydrate

Gas Lift System

Gas Lift Injection

Gas Oil

Gas Oil Contact

Gas Oil Ratio (GOR)

Gas on Gas Competition (GOG)

Gas Price

Gas Processing

Gas Processors Association (GPA)

Gas Treating Facility

Gas Turbine

Gas Turbine Generator

Gas Water Contact

Gas Well

Gaseous

Gaseous Diffusion

Gasification

Gasifier

Gasket

Gaslighting

Gasohol

Gasoline

Gasoline Blending

Gasoline Price

Gassing

Gastech

Gastritis

Gate Valve

Gateway

Gateway Exchange

GATS (General Agreement on Trade in Services)

GATT (General Agreement on Tariffs and Trade)

Gauge

Gauge Hole

Gauge Pressure

Gauge Tank

Gauss (G or Gs)

Gaussian Model

Gay-Lussac's law

GCC

GDP (Gross Domestic Product)

GDP Deflator (or GDP Price Index) GDPR (General Data Protection Regulation)

GDSI (Gas Dispersion and Smoke Ingress) Analysis

Gear

Gear Pump

Gel

Gel Type Battery

Gene

Gene Expression

Gene Flow

Gene Therapy

General Average

General Corrosion (or Uniform Corrosion)

General Damages

General Exhaust (or Dilution Ventilation)

General Government Sector

General Obligation

General Terms and Conditions

Generate

Generation

Generative AI

Generator

Genetic

Genetic Effect

Genetic Engineering

Genetic Fingerprinting (or DNA Fingerprinting)

Genetic Material

Genetic Resource

Genetics

Genocide

Genome

Genotoxic

Genset (Generator Set)

Gentrification

Genuine

Geocoding

Geodetic Datum

Geography

Geologic Hazard

Geologic Map

Geology

Geometric

Geometric Centre

Geometric Growth

Geometric Isomer

Geometric Mean

Geometry

Geopolitics

Geosteer

Geotechnical (Geotech) Engineering

Geotechnical Survey

Geothermal Energy

Geothermal Gradient

Geothermal Heat Pump

Geothermal Power Plant

Germ

Germ Cell

Germanium (Ge)

Germicidal

Geyser

GHS (Globally Harmonized System)

Gibbs Energy

Giffen Good   Gig Economy

Giga (G)

Gigantic

Gin Pole

Ginger Group

Gini Index (or Gini Coefficient)

Girder

GIS (Global Industry Services)

GIS (Geographic Information System)

Glacier

Gland

Glare

Glass

Glazing

Global

Global Bond

Global Commons

Global Complexity Index (ECI and PCI)

Global Insolation (or Solar Radiation)

Global Pricing Model (GPM)

Global Warming

Global Warming Potential of a Gas

Globalisation

Globe Valve

Gloss Paint

Glossary

Glucose (C6H12O6)

Glue

Glut

Glycogen

Glycol

GM (Genetic Modification)

GMO (Genetically Modified Organism)

GNP (Gross National Product)

Goal

Going Concern

Gold (Au or GC)

Gold Loan

Gold Swap

Goldilocks

Good

Good Code

Good Engineering Practice (GEP)

Good Governance

Good Industry Practice (GIP)

Goods

Goods and Services Account

Goodwill

Google

Google AdSense

Gout

Govern

Governance

Governing Law

Government

Government Gross Debt

Government Guarantee

Government Net Debt

Governor

GPS (Global Positioning System)

Grace

Grace Time (or Period)

Grade

Graham's Law

Grain

Grain Alcohol

Gram (G)

Grant

Grant Element

Graphene

Graphic

Graphical Evaluation and Review Technique (GERT)

Graphite

Graphitic Corrosion

Graphitization

Grass Roots Plant

Gravel

Gravimetric Analysis 

Gravitational Acceleration (g)

Gravitational Force

Gravitational Potential Energy

Gravitational Wave

Gravity (or Gravitation)

Gravity Flow

Gray (Gy)

Gray Hydrogen

Gray Iron or Grey Cast Iron

Gray Rhino vs. Black Swan GRC (Governance, Risk and Compliance)

GRE (Glass Reinforced Epoxy)

Greedflation

Greek Alphabet

Green Ammonia

Green Ban

Green Belt

Green Certificate

Green Chemistry

Green Diesel

Green Economy

Green Energy

Green Gas

Green GDP

Green Hydrogen

Green Power

Green Pricing

Green Revolution

Green Tech (or Green Technology)

Greenfield

Greenfield Plant Greenflation

Greenhouse Climate Response Index

Greenhouse Effect

Greenhouse Gas

Greywater

Grid

Grid Connected System

Grid Energy Storage

Grid Line (or Gridline)

Grind

Grinder Pump

Grit

Grit Blasting

Gross

Gross Accumulation

Gross Calorific Value (GCV)

Gross Capital Formation

Gross Debt

Gross Heating Value (GHV)

Gross Income

Gross Margin

Gross National Income (GNI)

Gross Rate of Return

Gross Tonnage (GT)

Gross Yield

Ground

Ground Loop

Ground Penetrating Radar (GPR)

Ground Reflection

Ground Roll

Ground State 

Ground Water

Groundbed

Grounding (or Earthing)

Grounding Diagrams for Instruments and Control Systems

Grounding Layout Drawing

Group

Group Comparison

Groupthink

GRP (Glass Reinforced Plastics)

GSA (General Services Administration)

GSI (Global Standards Initiative)

GTL (Gas to Liquid)

Guarantee

Guaranteed Annuity

Guaranteed Bond

Guaranteed Maximum (G-Max) Price

Guess

Guesstimation

Guidance

Guide

Guided Wave Testing (GW)

Guideline

Gulf of Mexico (GOM)

Gulf Publishing Company

Gunwale

Guru

Gust

Guy Wire