Engineering Glossary: G
38 definitions in plain language.
38 terms beginning with G. Use the filter to narrow the list, or the letters to jump to another part of the glossary.
38 terms
- Gain #
- The ratio of output to input of an amplifier or filter, often in decibels. Electronics
- Gain margin #
- How much the loop gain can increase before a feedback system becomes unstable. Automation, controls and robotics
- Galvanic corrosion #
- Corrosion of the more active metal when two different metals are in contact in an electrolyte. Materials, manufacturing and measurement
- Galvanizing #
- Coating steel with zinc, by hot dipping or electroplating, to protect it from rust. Materials, manufacturing and measurement
- Gantt chart #
- A bar chart that shows tasks against time. Math, units, quality and workshop
- Gas constant #
- The constant in the ideal gas law; the universal value is 8.314 J/mol·K and the specific value is that divided by the molar mass. Fluids, heat and thermodynamics Read more: Physical Constants
- Gasket #
- A sheet or ring of soft material that seals the joint between two flat surfaces. Math, units, quality and workshop
- Gate #
- The opening through which molten plastic enters the mold cavity. Materials, manufacturing and measurement
- Gate threshold voltage #
- The gate voltage at which a MOSFET begins to conduct. Electronics
- Gateway #
- A device that connects networks that use different protocols or addresses. Automation, controls and robotics
- Gauge block #
- A precisely ground block of known thickness used to calibrate instruments and set up measurements. Also called a slip gauge. Materials, manufacturing and measurement
- Gauge pressure #
- Pressure measured relative to the local atmosphere; a tire gauge reads gauge pressure. Fluids, heat and thermodynamics
- G-code #
- The programming language of CNC machines, made of commands like G01 (linear move) and M03 (spindle on). Materials, manufacturing and measurement Read more: G-code Viewer and Run Time Estimator
- GD&T #
- Geometric dimensioning and tolerancing: a symbolic language for specifying the form, orientation and location of features. Materials, manufacturing and measurement Read more: GD&T
- Gear #
- A toothed wheel that transmits motion and torque by meshing with another. Mechanical design and mechanics Read more: Gear Basics and Terminology
- Gearbox #
- A set of gears in a housing that changes the speed and torque of a motor. Automation, controls and robotics
- Gear ratio #
- The ratio of the teeth on the driven gear to the teeth on the driving gear; it sets the change in speed and torque. Mechanical design and mechanics
- Gear train #
- A series of gears connected to transmit motion and change speed or direction. Mechanical design and mechanics
- Generator #
- A machine that turns mechanical energy into electrical energy. Electrical power and machines
- Gerber file #
- The standard file format used to send PCB layer designs to a manufacturer. Electronics
- Glass transition temperature #
- The temperature at which an amorphous plastic changes from hard and glassy to soft and rubbery. Materials, manufacturing and measurement
- Go/no-go gauge #
- A gauge with a go end that must fit and a no-go end that must not, used to check a hole or thread quickly. Materials, manufacturing and measurement
- Goodman diagram #
- A plot of mean stress against alternating stress that shows safe combinations for fatigue loading. Mechanical design and mechanics
- GPIO #
- General-purpose input/output: a pin that software can set as an input or an output. Programming, data and computing
- Gradient descent #
- An optimization method that repeatedly moves in the direction that reduces the error fastest. Programming, data and computing
- Grain size #
- The average size of the crystals in a metal; finer grains usually give higher strength and toughness. Materials, manufacturing and measurement
- Grashof condition #
- A rule for four-bar linkages: if the shortest plus the longest link is less than the sum of the other two, one link can rotate fully. Mechanical design and mechanics
- Gravity #
- The force of attraction between masses; on Earth it gives a downward acceleration of about 9.81 m/s². Math, units, quality and workshop Read more: Physical Constants
- Gray iron #
- Cast iron with graphite flakes, easily machined, good at damping vibration and weak in tension. Materials, manufacturing and measurement
- Grease #
- A lubricant made of oil thickened with soap or another thickener. Math, units, quality and workshop
- Grid #
- The interconnected network that carries electricity from generators to users. Electrical power and machines
- Grinding #
- Removing small amounts of material with an abrasive wheel to give a precise size and fine finish. Materials, manufacturing and measurement
- Ground fault #
- An unintended connection between a live conductor and earth. Electrical power and machines
- Grounding #
- The American term for earthing: connecting equipment to ground. Electrical power and machines
- Grounding (electronics) #
- The choice of the reference return path for signals and power in a circuit. Electronics
- Ground loop #
- An unwanted current loop formed when a circuit is grounded at more than one point, which introduces noise. Electronics
- Ground plane #
- A large area of copper on a PCB used as a low-impedance return for signals. Electronics
- Gyroscopic effect #
- The tendency of a spinning body to keep the direction of its axis, and to precess when a torque is applied. Mechanical design and mechanics