EF or ef may refer to:
Arts and entertainment
*
Ef (band), a post-rock band from Sweden
* ''
Ef: A Fairy Tale of the Two.'', a Japanese adult visual novel series by Minori, or its anime adaptations
Businesses and organizations
*
Eagle Forum, an anti-feminist conservative interest group
*
Earth First! movement, in environmentalism
*
Eastern Fare, a music institution and production house in Bangalore, India
*
EF Education First an international education organization
*
The Elias Fund, a non-profit organization
*
Far Eastern Air Transport (IATA code EF)
Linguistics
*
Ef (Cyrillic) (Ф, ф), a letter in the Cyrillic alphabet
*
F, a Latin letter
Science
Biology and psychology
*
Ejection fraction, in cardiovascular physiology
*
Elongation factors, proteins that are important in protein synthesis
*
Executive functions, a theorized cognitive system in psychology that controls and manages other cognitive processes
Physics
*
Electric field
An electric field (sometimes E-field) is the physical field that surrounds electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to the physical field fo ...
, in physics
*
Exafarad, an SI unit of electric capacitance
*
Fermi energy or
Fermi level
The Fermi level of a solid-state body is the thermodynamic work required to add one electron to the body. It is a thermodynamic quantity usually denoted by ''µ'' or ''E''F
for brevity. The Fermi level does not include the work required to remove ...
(''E''
F), both concepts in quantum mechanics
Other sciences
*
Ecological footprint
The ecological footprint is a method promoted by the Global Footprint Network to measure human demand on natural capital, i.e. the quantity of nature it takes to support people or an economy. It tracks this demand through an ecological accounti ...
, the measure of the demand the population has on the environment
*
Enhanced Fujita scale (EF scale), an improved version of the Fujita scale used to rate the intensity of tornadoes
*
Ice cap climate, which is abbreviated to EF in the Köppen climate classification
Technology
*
Canon EF camera
The Canon EF is a manual focus 35mm 35 mm may refer to:
* 135 film, a type of still photography format commonly referred to as 35 mm film
* 35 mm movie film, a type of motion picture film stock
* 35MM 35 mm may refer to:
* 135 fil ...
, a manual focus 35mm SLR
*
Canon EF lens mount, Canon's auto-focus lens mount
*
Entity Framework, an object-relational mapping (ORM) framework for the .NET Framework
Other uses
*
Extraordinary Form, a phrase used to describe the Catholic liturgy of the 1962 Roman Missal
*
Era Fascista, the Italian fascist calendar
* Extra fine, a
condition of a coin
*
Eurofurence, a furry convention in Berlin, Germany
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