Technology glossary

Electrode Fouling

The accumulation of minerals, organic matter or reaction products on an electrode surface, which can block active sites, increase resistance and reduce electrochemical performance.

Electroencephalography(EEG)

A method that records electrical activity produced by the brain using electrodes placed on or near the scalp.

Electroforming

A process that deposits metal onto a removable form using an electric current until the deposited layer becomes a self-supporting component.

Electron-Beam Irradiation(EBI)

A process that exposes material or air to high-energy electrons to damage microbes or alter materials.

Electron-Transport Layer(ETL)

A layer in an electronic or photovoltaic device that selectively carries electrons from an active material to an electrode while limiting the movement of positive charge carriers. Its energy levels, conductivity, and interface quality strongly affect device efficiency and stability.

Electronic Door Latch

A door-locking mechanism that uses an electrical signal from a button, sensor or control module to release the latch. Vehicles still need a mechanical backup because crash damage or loss of low-voltage power can stop the electronic command.

Emissivity Control

The adjustment of a surface's ability to emit thermal radiation. Coatings, structures, phase-change materials, or electronic controls can vary emissivity to manage heating and cooling in buildings, spacecraft, sensors, and energy systems.

Enabled Emissions

Additional greenhouse gas emissions that become possible when a technology lowers costs, raises productivity or expands a carbon-intensive activity. The term includes indirect effects, such as AI making additional fossil-fuel extraction economically viable.

Energy Turnover Point

In atmospheric predictability research, a proposed time by which incoming energy has propagated through the atmosphere widely enough to erase information about an exactly known initial state. It is a theoretical concept and is not an operational forecast horizon.

Engineered Living Material

A material that uses living cells as active components to sense, respond, grow or repair.

Engineering Copilot

An AI-based assistant that supports engineering tasks such as drafting designs, writing code, analyzing requirements, running calculations, searching documentation, or checking work. Its outputs require validation because errors, missing context, or unsuitable assumptions can affect safety and performance.

Ensemble Weather Forecast

A set of weather predictions produced with varied initial conditions or model configurations to estimate the range and probability of possible atmospheric outcomes.

Enterotype

A statistical grouping of gut microbial communities based on recurring patterns in their composition. Enterotypes are broad clusters rather than fixed diagnoses or sharply separated biological types.

Enucleation

The final maturation step in which a developing mammalian red blood cell removes its nucleus.

Environmental Justice

The principle that environmental risks and benefits should not be distributed unfairly across communities.

Environmental Moratorium

A temporary suspension of a project, activity, permit, or development category to prevent potential environmental harm while evidence, regulation, or impact assessments are reviewed. It pauses action rather than permanently banning it.

Enzyme Cascade

A sequence of enzyme-catalyzed reactions in which the product of one step becomes the input for the next.

Ephemeris

In satellite navigation, ephemeris data describes a satellite's precise orbit so a receiver can calculate where that satellite was when its signal was transmitted. GPS satellites broadcast updated ephemeris information as part of their navigation messages.

Equipment Authorization

A regulatory approval process used to determine whether radio-frequency devices can legally enter a market.

Equity Retention Program

A compensation arrangement that grants company equity to encourage employees to remain after an acquisition or other major transition.

Error-Corrected Qubit

A logical quantum bit protected by error-correction methods that distribute information across multiple physical qubits.

Erythropoiesis

The biological process that produces red blood cells from precursor cells.

eSIM Remote Provisioning

The controlled process for downloading, activating, switching and managing mobile-operator profiles on an embedded SIM without replacing a physical card.

Evolutionary Burst

A relatively short period in which a lineage undergoes unusually rapid anatomical or functional change.

Excessive Daytime Sleepiness(EDS)

Persistent difficulty staying awake or alert during normal daytime activities. It can result from sleep deprivation, sleep disorders, medicines or medical conditions, and becomes an urgent safety concern when it affects driving or other vigilance-critical tasks.

Excitatory Neurogenesis

The developmental production of neurons that generally increase the likelihood that connected cells will fire electrical signals, commonly through glutamate-based signaling in the cortex.

Exerkine

A signaling molecule released or altered in response to exercise that can carry information between tissues. Exerkines include proteins, peptides, metabolites, and other factors, but detecting one after exercise does not by itself prove that it causes a health benefit.

Facial Age Estimation

A computer-vision process that predicts an age range from facial features without necessarily identifying the person. Accuracy varies across ages and demographic groups, so it should not be treated as exact proof of age.

Facial Constitutional Challenge

A lawsuit arguing that a law is unconstitutional in its text or broad operation, rather than only unconstitutional when applied to one person’s specific circumstances.

Fair Use

A doctrine in United States copyright law that can permit limited use of protected works depending on purpose, nature, amount, and market effect.