Latin letters used in mathematics

Aa

• A represents:
• *the first point of a triangle
• *the digit "10" in hexadecimal and other positional numeral systems with a radix of 11 or greater
• *the unit ampere for electric current in physics
• *the area of a figure
• *the mass number of an element in chemistry
• *the Helmholtz free energy of a closed thermodynamic system of constant pressure and temperature
• *a vector potential, in electromagnetics it can refer to the magnetic vector potential
• *an Abelian group in abstract algebra
• *the Glaisher–Kinkelin constant
• ? represents the algebraic numbers or affine space in algebraic geometry
• a represents:
• *the first side of a triangle
• *the scale factor of the expanding universe in cosmology
• *the acceleration in mechanics equations
• *the x-intercept of a line using the line equation
• *the unit are for area
• *the unit prefix atto
• *the first term in a sequence or series

  Bb

• B represents:
• *the digit "11" in hexadecimal and other positional numeral systems with a radix of 12 or greater
• *the second point of a triangle
• *a ball or ? )
• * a basis of a vector space or of a filter )
• * in econometrics and time-series statistics it is often used for the backshift or lag operator, the formal parameter of the lag polynomial
• *the magnetic field, denoted or
• B with various subscripts represents several variations of Brun's constant and Betti numbers; it can also be used to mean the Bernoulli numbers
• b represents:
• *the second side of a triangle
• *The impact parameter in nuclear scattering
• *the y-intercept of a line using the line equation
• *usually with an index, sometimes with an arrow over it, a basis vector

  Cc

• C represents:
• * the third point of a triangle
• * the digit "12" in hexadecimal and other positional numeral systems with a radix of 13 or greater
• * the unit coulomb of electrical charge
• * capacitance in electrical theory
• * with indices denotes the number of combinations, a binomial coefficient
• * together with a degree symbol represents the Celsius measurement of temperature = °C
• * the circumference of a circle or other closed curve
• * the complement of a set
• C represents:
• * an arbitrary category
• ℂ represents the set of complex numbers
• A vertically elongated C with an integer subscript n sometimes denotes the n-th coefficient of a formal power series.
• c represents:
• * the unit prefix centi
• * the molar concentration in chemistry
• c represents:
• * the speed of light in a vacuum
• * the third side of a triangle
• Lower case Fraktur denotes the cardinality of the set of real numbers, or, equivalently, of the power set of natural numbers

  Dd

• D represents
• *the digit "13" in hexadecimal and other positional numeral systems with a radix of 14 or greater
• *diffusion coefficient or diffusivity in dimensions of
• *the differential operator in Euler's calculus notation
• d represents
• *the differential operator
• *the unit day of time
• *the difference in an arithmetic sequence
• *a metric operator/function
• *the diameter of a circle

  Ee

• E represents:
• *the digit "14" in hexadecimal and other positional numeral systems with a radix of 15 or greater
• *an exponent in decimal numbers. For example, 1.2E3 is 1.2×10³ or 1200
• *the set of edges in a graph or matroid
• *the unit prefix exa
• *energy in physics
• *electric field denoted or
• * electromotive force, refers to voltage.
• *an event
• *in statistics, the expected value of a random variable
• e represents:
• *Euler's number, a transcendental number equal to 2.71828182845... which is used as the base for natural logarithms
• *a vector of unit length, especially in the direction of one of the coordinates axes
• *the elementary charge in physics
• *an electron, usually donated e⁻ to distinguish against a positron e⁺
• *the eccentricity of a conic section
• *the identity element in a group

  Ff

• F represents
• *the digit "15" in hexadecimal and other positional numeral systems with a radix of 16 or greater
• *the unit farad of electrical capacity
• *the Helmholtz free energy of a closed thermodynamic system of constant pressure and temperature
• * together with a degree symbol represents the Fahrenheit measurement of temperature = °F
• F represents
• *force in mechanics equations
• *_pF_q is a hypergeometric series
• *the probability distribution function in statistics
• *a Fibonacci number
• * an arbitrary functor
• f represents:
• *the unit prefix femto
• f represents:
• *the generic designation of a function

  Gg

• G represents
• *an arbitrary graph, as in: G
• *an arbitrary group
• *the unit prefix giga
• *Newton's gravitational constant
• *the Einstein tensor
• *the Gibbs energy
• *the centroid of a triangle
• *Catalan's constant
• g represents:
• *the generic designation of a second function
• *the acceleration due to gravity on Earth

  Hh

• H represents:
• *a Hilbert space
• *the unit henry of magnetic inductance
• *the homology and cohomology functor
• *the enthalpy
• *the entropy of information
• *the orthocenter of a triangle
• *a partial sum of the harmonic series
• *magnetic field, denoted.
• H₀ represents Hubble's parameter as measures today
• ℍ represents the quaternions
• ℋ represents the Hamiltonian in Hamiltonian mechanics
• h represents:
• *the class number in algebraic number theory
• *a small increment in the argument of a function
• *the unit hour for time
• *the Planck constant
• *the unit prefix hecto
• *the generic designation of a third function
• *the altitude of a triangle

  Ii

• I represents:
• *the closed unit interval, which contains all real numbers from 0 to 1, inclusive
• *the identity matrix
• *the Irradiance
• *the moment of inertia
• *Intensity in physics
• *the incenter of a triangle
• I represents:
• * the index of an indexed family
• i represents:
• *the imaginary unit, a complex number that is the square root of −1
• *a subscript to denote the ith term in a sequence or list
• *the index to the elements of a vector, written as a subscript after the vector name
• *the index to the rows of a matrix, written as the first subscript after the matrix name
• *an index of summation using the sigma notation
• *the unit vector in Cartesian coordinates going in the X-direction, usual bold i

Jj

• J represents:
• *the unit joule of energy
• *the current density in electromagnetism denoted.
• *the Radiosity in thermal mechanics
• J represents:
• * the scheme of a diagram in category theory
• j represents:
• *the index to the columns of a matrix, written as the second subscript after the matrix name
• *in electrical engineering, the square root of −1, instead of i
• *in electrical engineering, the principal cube root of 1:

  Kk

• K represents:
• *the unit kelvin of temperature
• *the functors of K-theory
• *an unspecified constant
• *a field in algebra
• *the area of a polygon
• k represents
• * the unit prefix kilo-
• * the Boltzmann constant, this is often represented as k_B to avoid confusion with
• * the Wavenumber of the wave equation
• * an integer, e.g. a dummy variable in summations, or an index of a matrix.
• * an unspecified constant
• * the spring constant of Hooke's law
• * the spacetime Curvature from the Friedmann equations in cosmology

  Ll

• L represents:
• *Length, used often in quantum mechanics as the size of an infinite square well
• *Angular momentum
• *the unit of volume the litre
• *the radiance
• *the space of all integrable real functions
• *the space of linear maps, as in L or L = End
• *the likelihood function
• *a formal language
• *the lag operator in statistics
• *a Lucas number
• l represents:
• *the unit of volume the litre
• *the length of a side of a rectangle or a rectangular prism
• *the last term of a sequence or series
• ℒ represents:
• *the Lagrangian
• *Exposure

  Mm

• M represents:
• * a manifold
• * a metric space
• * a matroid
• *the unit prefix mega-
• * the Madelung constant for crystal structures held by ionic bonding
• m represents:
• *the number of rows in a matrix
• *the slope in a linear regression or in any line
• *the mass in mechanics equations
• *the unit metre of length
• *the unit prefix milli
• *a median of a triangle

  Nn

• N represents
• *the unit newton of force
• *the Neutron number
• *the Particle number in thermodynamics
• *The number of particles of a thermodynamical system
• *the nine-point center of a triangle
• N_A represents the Avogadro constant which is the number of entities in one mole and is 6.022 141 79 × 10,²³ mol ⁻¹
• ℕ represents the natural numbers
• n represents
• *the number of columns in a matrix
• *the "number of" in algebraic equations.
• *A neutron, often shown as ¹₀n
• *the Number density of particles in a Volume
• *the unit prefix nano
• *the nth term of a sequence or series
• *the principal quantum number

  Oo

• O represents
• *the order of asymptotic behavior of a function ; see Big O notation
• * — the origin of the coordinate system in Cartesian coordinates
• *the circumcenter of a triangle or other cyclic polygon, or more generally the center of a circle
• o represents
• *the order of asymptotic behavior of a function ; see Little o notation
• *the order of an element in a group

  Pp

• P represents:
• *the pressure in physics equations
• *the unit prefix peta
• *probability in statistics and statistical mechanics
• *an arbitrary point in geometry
• ℙ represents
• *the prime numbers
• *projective space
• *a probability
• p represents
• *the unit prefix pico
• *a proton, often p⁺ or p
• *the linear momentum in physics equations
• *the perimeter of a triangle or other polygon

  Qq

• Q represents:
• * heat energy
• ℚ represents the rational numbers
• q represents:
• * the deceleration parameter in cosmology
• * electric charge of a particle

  Rr

• R represents:
• *the Ricci tensor
• *the circumradius of a cyclic polygon such as a triangle
• *an arbitrary relation
• ℝ represents the set of real numbers and various algebraic structures built upon the set of real numbers, such as
• r represents:
• *the radius of a circle or sphere
• *the inradius of a triangle or other tangential polygon
• *the ratio of a geometric series
• *the separation of two objects, for example in Coulomb's law

  Ss

• S represents
• *a sum
• *the unit siemens of electric conductance
• *the unit sphere
• *the scattering matrix
• * entropy
• s represents:
• *an arclength
• *the displacement in mechanics equations
• *the unit second of time
• *a complex variable s = σ + i t in analytic number theory
• *the semiperimeter of a triangle or other polygon
• ? represents a system's action in physics

  Tt

• T represents:
• *the top element of a lattice
• *a tree
• *temperature in physics equations
• *the unit tesla of magnetic flux density
• *the unit prefix tera
• *the stress–energy tensor
• *tension in physics
• *an arbitrary monad
• t represents:
• *time in graphs, functions or equations
• *a term in a sequence or series
• *the imaginary part of the complex variable s = σ + i t in analytic number theory
• *the sample statistic resulting from a Student's t-test

  Uu

• U represents:
• *a U-set which is a set of uniqueness
• *a unitary operator
• *in thermodynamics, the internal energy of a system
• *a forgetful functor
• U represents the unitary group of degree n
• ∪ represents the union operator

  Vv

• V represents:
• *volume
• *the unit volt of voltage
• *the set of vertices in a graph
• *a vector space
• v represents the velocity in mechanics equations

  Ww

• W represents:
• *the unit watt of power
• *work, both mechanical & thermodynamical
• *in thermodynamics, the number of possible quantum states in Boltzmann's entropy formula
• w represents:
• * the coordinate on the fourth axis in four-dimensional space.

  Xx

• X represents
• *a random variable
• *a triangle center
• x represents
• *a realized value of a random variable
• *an unknown variable, most often from the set of real numbers, while a complex unknown would rather be called z, and an integer by a letter like m from the middle of the alphabet.
• *the coordinate on the first or horizontal axis in a Cartesian coordinate system, or the viewport in a graph or window in computer graphics.

  Yy

• Y represents:
• *the unit prefix yotta-
• Y represents:
• *a second random variable
• y represents:
• *the unit prefix yocto-
• y represents:
• *a realized value of a second random variable
• *a second unknown variable
• *the coordinate on the second or vertical axis in a linear coordinate system, or in the viewport of a graph or window in computer graphics.

  Zz

• Z represents:
• *the unit prefix zetta
• *the atomic number in chemistry and physics
• *a standardized normal random variable in probability theory and statistics
• *The partition function in statistical mechanics
• *in meteorology, the radar reflectivity factor
• ℤ represents the integers
• z represents:
• *the unit prefix zepto
• *the coordinate on the third or vertical axis in three dimensional space
• *the view depth in computer graphics, see also "z-buffering"
• *the argument of a complex function, or any other variable used to represent a complex value
• * in astronomy, wavelength redshift
• *a third unknown variable