List of letters used in mathematics and science

Some common conventions:
* Intensive quantities in physics are usually denoted with minuscules, while extensive are denoted with capital letters.
* Most symbols are written in italics.
* Vectors are bold.
* Sets of numbers are blackboard bold.

Latin

Å - Ångström,

A - Ampere, Area, a Blood type, a Spectral type, Vector potential, Work,

B - B meson, a Blood type, Boron, Luminance, Magnetic field, a Spectral type,

C - Carbon, Degrees Celsius, Set of complex numbers, Coulomb, Molar heat capacity (C_p), a Programming language, Specific heat capacity,

D - Deuterium, Differential operator, Electric displacement,

E - Electric field, Energy, SI prefix: (exa-), Expected value,

F - degrees Fahrenheit, Farad, Fluorine, Force, Helmholtz free energy, a Spectral type,

G - Einstein tensor, SI prefix: (giga-), Gibbs free energy, Gravitational constant, Green's function, Momentum, a Spectral type,

H - Auxiliary magnetic field, Enthalpy, Hamiltonian, Hankel function, Heaviside step function, Henry, Higgs boson, Homology group, Hubble constant, Hydrogen, Set of Quaternions,

I - Current, Iodine, Impulse, Luminous intensity, Moment of inertia,

J - Angular momentum, Bessel function of the first kind, Current, Joule,

K - Kaon, Kelvin, Potassium, Sectional curvature,a Spectral type,

L - Angular momentum, Inductance, Lagrangian, Litre, a Spectral type,

M - Magnetization, Mass, SI prefix: (mega-), a Spectral type, Torque,

N - Avogadro's number (N_A), Bessel function of the second kind, Set of natural numbers, Newton, Nitrogen, Normal distribution, Normal vector,

O - Big O notation, a Blood type, Oxygen, a Spectral type,

P - Legendre polynomial, Luminous flux, Phosphorus, Polarization, Power, Pressure, Probability, Projection,

Q - Electric charge, (Quantity of) heat, Set of rational numbers, Flow rate,

R - Curvature tensor, Electrical resistance, Radius, Set of real numbers,

S - Area, Entropy, Siemens, Sphere, Spin operator, Sulfur, Symmetric group,

T - a Spectral type, Temperature, Tesla, Tritium,

U - Potential energy, Uranium, Unitary operator,

V - Potential energy, Vanadium, Volt, Voltage, Volume,

W - Energy, Lambert's W function, Tungsten, Watt, W boson, Work, Work function,

X - Random variable,

Y - Bessel function of the second kind, SI prefix: (yotta-), Yttrium,

Z - Atomic number, Impedance, Set of integers, Partition function (statistical mechanics), Partition function (quantum field theory), Z boson, SI prefix: (zetta-),

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a - SI prefix: (atto-), Acceleration, Reflectance,

b - Bottom quark,

c - SI prefix: (centi-), Charm quark, Speed of light, Speed of sound,

d - SI prefix: (deci-), Distance, Down quark, Infinitesimal quantity, differential operator,

e - Napier's constant, Electron, Electric charge,

f - SI prefix: (femto-), Frequency,

g - gram, Gravitational acceleration, Gravitational field, Distance metric of spacetime,

h - Height, Hour, Planck's constant, Spherical Hankel function,

i - Imaginary unit, Unit vector, Current,

j - Current and current density, Imaginary unit, Radiant intensity, Spherical Bessel function of the first kind, Unit vector,

k - Boltzmann constant (k_B), Imaginary unit (quaternion), SI prefix: (kilo-), Wave vector, Unit vector,

l - Length, Litre, Mean free path,

m - magnitude, Mass, SI prefix: (milli-), Metre, Minute,

n - SI prefix: (nano-), Neutron, Refractive index, Spherical Bessel function of the second kind,

o - small o notation.

p - Electric dipole moment, Momentum, SI prefix: (pico-), Proton,

q - Electric charge, Generalized coordinate,

r - Position (vector), Radial polar coordinate, Radius,

s - Second, Strange quark,

t - Period, Time, Top quark,

u - Up quark,

v - Velocity,

w - Velocity,

x - Position coordinate,

y - Position coordinate, SI prefix: (yocto-),

z - Complex number, Position coordinate, SI prefix: (zepto-),

Greek

Β - Beta function,

Γ - Angular momentum, Gamma function, Christoffel symbols,

Δ - A macroscopic change in the value of a variable, Laplace operator, Delta particle

Θ - Heaviside step function,

Λ - Iwasava algebra, Lorentz transformation, Lambda Hyperon

Ξ - Cascade Hyperon

Π - Product,

Σ - Sum, Surface, Sigma Hyperon

Φ - Alternative symbol for Quantum mechanical wavefunction,

Ψ - Quantum mechanical wavefunction

Ω - Chaitin's constant, Ohm, Solid angle, Omega Hyperon

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α - Alpha particle, Fine structure constant, Angular acceleration,

β - Beta particle, Inverse temperature,

γ - Euler-Mascheroni constant, Gamma-ray (Photon), Photon, Relativistic gamma factor,

δ - Dirac delta function, Infinitesimal quantity, Kronecker delta,

ε - Infinitesimal quantity, Permittivity,

ζ - Damping Ratio, Riemann zeta function

η - Distance metric of flat spacetime, Efficiency, Dynamic viscosity,

θ - Angle, Angular polar coordinate, Temperature,

ι -

κ - Gravitational constant,

λ - Half-life, Lagrangian multiplicator, Lambda expression,
Thermal conductivity, Wavelength,

μ - Absorption coefficient, Chemical potential, Magnetic dipole moment, Mean, SI prefix: (micro-), Micron, Muon, Permeability, Reduced mass,

ν - Frequency, Kinematic viscosity, Neutrino,

ξ -

ο -

π - Fundamental group, Conjugate momentum, Homotopy groups, Number π, Pion, Prime-counting function, Projection

ρ - Density, Electrical resistivity, Radial polar coordinate,

σ - Cross section, Electrical conductivity, Spin, Standard deviation, Stefan-Boltzmann constant,

τ - Tau lepton, Torque, Shear stress, Time constant

υ -

φ - Angular polar coordinate, Electric potential, Euler's totient function, Golden mean, Phase, Potential energy,

χ - Electric susceptibility,

ψ - Quantum mechanical wavefunction, J/ψ particle

ω - Frequency (in radians/s), angular velocity,

More

Ш - Shafarevich-Tate group (Ш("G")),

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ℵ - Cardinality of infinite sets

ב - Cardinality of infinite sets

∂ - Partial derivative.