T, or t, is the twentieth letter of the English alphabet. T may also refer to:

Codes and units

* T,

Tera- A metric prefix is a unit prefix that precedes a basic unit of measure to indicate a multiple or submultiple of the unit. All metric prefixes used today are decadic. Each prefix has a unique symbol that is prepended to any unit symbol. The pre ...

as in one trillion * T, the symbol for "True" in

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the study of deductively valid inferences or logical truths. It examines how conclusions follow from premises based on the structure o ...

* T, the usual symbol for period, the reciprocal of

frequency Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio ...

* T, the symbol for Tesla, the SI unit of magnetic field * t, the SI symbol for

tonne The tonne ( or ; symbol: t) is a unit of mass equal to 1,000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the s ...

or ''metric ton'' * t, the usual symbol for

time Time is the continuous progression of existence that occurs in an apparently irreversible process, irreversible succession from the past, through the present, and into the future. It is a component quantity of various measurements used to sequ ...

* t, the angular coordinate of the

polar coordinate system In mathematics, the polar coordinate system specifies a given point in a plane by using a distance and an angle as its two coordinates. These are *the point's distance from a reference point called the ''pole'', and *the point's direction from ...

(usually ϕ or θ) is sometimes denoted by t *

\tau

, the symbol for

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

* ⊤, the top element of a partially ordered set * T, short for

tablespoon A tablespoon (tbsp., Tbsp., Tb., or T.) is a large spoon. In many English-speaking regions, the term now refers to a large spoon used for serving; however, in some regions, it is the largest type of spoon used for eating. By extension, the ter ...

* t, short for teaspoon

Names

* Titus (praenomen), common name throughout Roman history, regularly abbreviated T

Entertainment

Literature

* ''T'', a novel by

Victor Pelevin Victor Olegovich Pelevin ( rus, Виктор Олегович Пелевин, p=ˈvʲiktər ɐˈlʲeɡəvʲɪtɕ pʲɪˈlʲevʲɪn; born 22 November 1962) is a Russian fiction writer. His novels include ''Omon Ra'' (1992), ''The Life of Insects' ...

* ''T'' (magazine), a fashion magazine, full name ''T: The New York Times Style Magazine'' * '' "T" Is for Trespass'', the twentieth novel in Sue Grafton's "Alphabet mystery" series, published in 2007 * T-unit, a grammatical term

Film and television

*Big T, ring name of American retired professional wrestler Ahmed Johnson (born 1963) * Mr. T (born 1952), American television actor *T, the production code for the 1965 ''Doctor Who'' serial '' Galaxy 4'' * The T logo for the American Spanish-language network

Telemundo Telemundo (; formerly NetSpan) is an American Spanish-language terrestrial television network owned by NBCUniversal Telemundo Enterprises, a division of NBCUniversal, which in turn is a wholly owned subsidiary of Comcast. It provides content ...

* ''T'' (2023 film), an Indian Odia-language film by Jitesh Kumar Parida

Music

* Ice-T (born 1958), American rapper and actor * ''T'' (Funker Vogt album), a 2000 aggrotech album by Funker Vogt * ''T'' (TVXQ album), a 2008 TVXQ album * ''T'' (Teflon Brothers album), a 2009 album by Finnish hip hop group Teflon Brothers * "t," an Iamamiwhoami song * T, abbreviation for

tutti ''Tutti'' is an Italian word literally meaning ''all'' or ''together'' and is used as a musical term, for the whole orchestra as opposed to the soloist. It is applied similarly to choral music, where the whole section or choir is called to sin ...

* T, abbreviation for

tenor A tenor is a type of male singing voice whose vocal range lies between the countertenor and baritone voice types. It is the highest male chest voice type. Composers typically write music for this voice in the range from the second B below m ...

* t, note abbreviation in tonic sol-fa for seventh scale degree * T-Babe, a virtual pop singer

Video games

* T (teen), a game rating from the Entertainment Software Rating Board which the board believes is suitable for those aged 13 years and older

Finance and business

AT&T AT&T Inc., an abbreviation for its predecessor's former name, the American Telephone and Telegraph Company, is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the w ...

, an American phone company with the New York Stock Exchange ticker symbol T *

T-Mobile International AG T-Mobile is the brand name used by some of the mobile communications subsidiaries of the German telecommunications company Deutsche Telekom, Deutsche Telekom AG in the Czech Republic (T-Mobile Czech Republic), Poland (T-Mobile Polska) and the Un ...

, mobile network operator based in Germany * T-Systems, German IT services company * T-Online, German Internet Service Provider *

Treasury A treasury is either *A government department related to finance and taxation, a finance ministry; in a business context, corporate treasury. *A place or location where treasure, such as currency or precious items are kept. These can be ...

(as in T-Bill, T-Bond, T-Note) * T, a mintmark for Nantes, France

Science

Biology and medicine

Troponin T Troponin T (shortened TnT or TropT) is a part of the troponin complex, which are proteins integral to the contraction of skeletal and heart muscles. They are expressed in skeletal and cardiac myocytes. Troponin T binds to tropomyosin and help ...

, one of the three

troponin Troponin, or the troponin complex, is a complex of three regulatory proteins (troponin C, troponin I, and troponin T) that are integral to muscle contraction in skeletal muscle and cardiac muscle, but not smooth muscle. Measurements of cardiac-spe ...

s * Haplogroup T (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup *

T cells T cells (also known as T lymphocytes) are an important part of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their ce ...

, part of the components of the immune system along with

B cells B cells, also known as B lymphocytes, are a type of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or inserted into the plasm ...

* T, the one-letter code used for

threonine Threonine (symbol Thr or T) is an amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH form when dissolved in water), a carboxyl group (which is in the deprotonated −COO− ...

, one of the 20 amino acids used in transcription of a polypeptide chain *

Thymine Thymine () (symbol T or Thy) is one of the four nucleotide bases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine. Thymine is also known as 5-methyluracil, a pyrimidine ...

, one of the four nucleic acids of

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

* T, gene and protein symbol for the transcription factor brachyury *

Thoracic vertebrae In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebra (anatomy), vertebrae of intermediate size between the ce ...

T-1 through T-12 *

T wave In electrocardiography, the T wave represents the repolarization of the ventricles. The interval from the beginning of the QRS complex to the apex of the T wave is referred to as the ''absolute refractory period''. The last half of the T wav ...

, the repolarization wave of cardiac ventricles in

electrocardiography Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity through repeated cardiac cycles. It is an electrogram of the heart which is a graph of voltage versus time of t ...

* T, a common abbreviation for the male sex hormone

testosterone Testosterone is the primary male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting se ...

Palaeontology

* T-rex, abbreviation for ''

Tyrannosaurus rex ''Tyrannosaurus'' () is a genus of large theropoda, theropod dinosaur. The type species ''Tyrannosaurus rex'' ( meaning 'king' in Latin), often shortened to ''T. rex'' or colloquially t-rex, is one of the best represented theropods. It live ...

Meteorology

Thunderstorm A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustics, acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorm ...

* T-number in the

Dvorak technique The Dvorak technique (developed between 1969 and 1984 by Vernon Dvorak) is a widely used system to estimate tropical cyclone intensity (which includes tropical depression, tropical storm, and hurricane/typhoon/intense tropical cyclone intensities ...

, a way to rate storm intensity

Physics and chemistry

* T, symbol for

tritium Tritium () or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.33 years. The tritium nucleus (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of the ...

, a radioactive isotope of hydrogen *

T-symmetry T-symmetry or time reversal symmetry is the theoretical symmetry of physical laws under the transformation of time reversal, : T: t \mapsto -t. Since the second law of thermodynamics states that entropy increases as time flows toward the futur ...

in particle physics * Class T, a cool brown dwarf class of stars * ΔT (disambiguation): a variety of meanings related to changes in a quantity denoted by T, such as time or temperature

Mathematics

* T score, a statistical term *

Student's t-distribution In probability theory and statistics, Student's distribution (or simply the distribution) t_\nu is a continuous probability distribution that generalizes the Normal distribution#Standard normal distribution, standard normal distribu ...

, statistical term * T, in

modal logic Modal logic is a kind of logic used to represent statements about Modality (natural language), necessity and possibility. In philosophy and related fields it is used as a tool for understanding concepts such as knowledge, obligation, and causality ...

\mathbb^n

, the ''n''-dimensional

torus In geometry, a torus (: tori or toruses) is a surface of revolution generated by revolving a circle in three-dimensional space one full revolution about an axis that is coplanarity, coplanar with the circle. The main types of toruses inclu ...

(

\mathbb^n/\mathbb^n

) *

\mathbb

, the

Circle group In mathematics, the circle group, denoted by \mathbb T or , is the multiplicative group of all complex numbers with absolute value 1, that is, the unit circle in the complex plane or simply the unit complex numbers \mathbb T = \. The circle g ...

*A^T, the

transpose In linear algebra, the transpose of a Matrix (mathematics), matrix is an operator which flips a matrix over its diagonal; that is, it switches the row and column indices of the matrix by producing another matrix, often denoted by (among other ...

of a

matrix Matrix (: matrices or matrixes) or MATRIX may refer to: Science and mathematics * Matrix (mathematics), a rectangular array of numbers, symbols or expressions * Matrix (logic), part of a formula in prenex normal form * Matrix (biology), the m ...

Technology and computing

* T (programming language), created in the early 1980s * T,

Toshiba is a Japanese multinational electronics company headquartered in Minato, Tokyo. Its diversified products and services include power, industrial and social infrastructure systems, elevators and escalators, electronic components, semiconductors ...

's mobile phones in Japan * T, an abbreviation for

telephone number A telephone number is the address of a Telecommunications, telecommunication endpoint, such as a telephone, in a telephone network, such as the public switched telephone network (PSTN). A telephone number typically consists of a Number, sequ ...

* t, an abbreviation for microblogging service

Twitter Twitter, officially known as X since 2023, is an American microblogging and social networking service. It is one of the world's largest social media platforms and one of the most-visited websites. Users can share short text messages, image ...

* t-distributed stochastic neighbor embedding, a machine learning algorithm for data visualization * T-pose, a default pose for a 3D model's skeleton before it is animated * Landing T, a ground signal that indicates the wind direction in aerodromes * Transfer (computing), in computer technology, a data transfer, often used to measure speed (e.g. megatransfers per second)

Transportation

Equipment

Ford Model T The Ford Model T is an automobile that was produced by the Ford Motor Company from October 1, 1908, to May 26, 1927. It is generally regarded as the first mass-affordable automobile, which made car travel available to middle-class Americans. Th ...

, a motor car produced in the U.S. 1908–1927 * NZR T class steam locomotives in New Zealand * OS T1000, an Oslo Metro train * T gauge, a scale for model railroad trains *

Tank locomotive A tank locomotive is a steam locomotive which carries its water in one or more on-board water tanks, instead of a more traditional tender (rail), tender. Most tank engines also have Fuel bunker, bunkers (or fuel tanks) to hold fuel; in a #Tender ...

Public transport

Japan

* Tanimachi Line, a subway service operated by the Osaka Metro, labeled Osaka Metro Tanimachi line symbol

* Tokyo Metro Tozai Line, a subway service operated by the Tokyo Metro, labeled *

Tsuyama Line The is a railway line operated by West Japan Railway Company (JR West) connecting and in Okayama Prefecture, Japan. Stations All-stations and limited-stop services called operate over the line. In the "Rapid" column in the table below, "O ...

, a railway service operated by West Japan Railway Company, with the official service symbol JRW oka-T

United States

Massachusetts Bay Transportation Authority The Massachusetts Bay Transportation Authority (abbreviated MBTA and known colloquially as "the T") is the public agency responsible for operating most public transportation services in Greater Boston, Massachusetts. The MBTA transit network in ...

(nicknamed the "T") * Pittsburgh Light Rail, commonly called the T * T (New York City Subway service) * T Line (Sound Transit) in Tacoma, Washington * T Third Street in San Francisco, California * Trinity Metro, formerly known as "The T", a transit agency serving Fort Worth, Texas and suburbs

Other countries

* Oslo Metro or * Stockholm Metro or

Phonetics

* the

International Phonetic Alphabet The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standard written representation ...

character for the

voiceless alveolar plosive The voiceless alveolar, dental and postalveolar plosives (or stops) are types of consonantal sounds used in almost all spoken languages. The symbol in the International Phonetic Alphabet that represents voiceless dental, alveolar, and postal ...

* � the IPA character representing the voiceless retroflex stop

Other uses

* "The T", a nickname for the rural part of Pennsylvania due to its shape when eliminating the Pittsburgh and Philadelphia Metropolitan Areas, also known by its slang term Pennsyltucky * Т, a letter of the Cyrillic alphabet * T-bone steak, the cut of meat * T-shirt, a type of clothing * T in the Park, an annual music festival, held in Kinross, Scotland and named after its main sponsor, the brewing company Tennents *

Crossing the T Crossing the ''T'' or capping the ''T'' is a classic naval warfare tactic used from the late 19th to the mid-20th centuries in which a line of warships crosses in front of a line of enemy ships to allow the crossing line to bring all their guns ...

, a classic naval warfare tactic * Stealing the 'T', an historic college prank as the "T" is stolen from the Tech Tower at the Georgia Institute of Technology * T (Tango), the military time zone code for UTC−07:00