Symbols & References

Greek letters

Greek letters are used throughout engineering, physics, and mathematics as standard symbols in formulas and equations. Click any letter to see its full reference page — with Unicode codes, LaTeX commands, copy buttons, and engineering examples.

Greek alphabet — all 24 letters
# Name Lowercase Uppercase LaTeX Common uses
1 Alpha α Α \alpha Thermal expansion, angular acceleration, fine-structure constant
2 Beta β Β \beta Beta radiation, compressibility, finance volatility
3 Gamma γ Γ \gamma Gamma radiation, Lorentz factor, shear strain, surface tension
4 Delta δ Δ \delta Change/difference (Δ), partial derivative, beam deflection
5 Epsilon ε Ε \epsilon Strain, permittivity, emissivity, eccentricity
6 Zeta ζ Ζ \zeta Damping ratio, Riemann zeta function, zeta potential
7 Eta η Η \eta Efficiency, dynamic viscosity, Carnot efficiency
8 Theta θ Θ \theta Plane angle, phase angle, polar coordinate, beam slope
9 Iota ι Ι \iota Inclusion map, index variable, array sequences
10 Kappa κ Κ \kappa Thermal conductivity, dielectric constant, curvature
11 Lambda λ Λ \lambda Wavelength, eigenvalue, decay constant, thermal conductivity
12 Mu μ Μ \mu Micro- prefix (10⁻⁶), friction coefficient, viscosity, mean
13 Nu ν Ν \nu Frequency, kinematic viscosity, Poisson’s ratio
14 Xi ξ Ξ \xi Damping ratio, random variable, generalised coordinate
15 Omicron ο Ο o Big-O notation, rarely used in technical formulas
16 Pi π Π \pi Circle constant (≈3.14159), product notation (Π), Pi theorem
17 Rho ρ Ρ \rho Density, electrical resistivity, correlation coefficient
18 Sigma σ Σ \sigma Summation (Σ), standard deviation, normal stress, conductivity
19 Tau τ Τ \tau Shear stress, torque, time constant, proper time
20 Upsilon υ Υ \upsilon Upsilon meson, alternative frequency symbol
21 Phi φ Φ \phi Golden ratio, electric potential, angle of friction, magnetic flux (Φ)
22 Chi χ Χ \chi Chi-squared test (χ²), electric & magnetic susceptibility
23 Psi ψ Ψ \psi Wave function (quantum), stream function, torsion angle
24 Omega ω Ω \omega Angular velocity, angular frequency, Ohm (Ω), natural frequency

Mathematical and engineering symbols

Mathematical and engineering symbols organised by category. Each group has its own reference page with copy buttons, Unicode codes, HTML entities and LaTeX commands for every symbol.

Symbol groups
# Category Symbols Description
1 Comparison Symbols ≥ ≤ ≠ ≈ ≡ ∝ Greater/less than, approximately equal, proportional to and more.
2 Arithmetic Symbols ± × ÷ √ ∛ ∞ Plus-minus, multiplication, division, roots, infinity and more.
3 Arrow Symbols → ← ⇒ ⇔ ↦ Direction, implication, mapping and bidirectional arrows.
4 Geometry & Angle Symbols ° ∠ ⊥ ∥ △ ≅ Degree, angle, perpendicular, parallel, triangle and more.
5 Set & Logic Symbols ∈ ∪ ∩ ∀ ∃ ∅ Element of, union, intersection, quantifiers and Boolean operators.
6 Integral & Calculus Symbols ∫ ∂ ∇ ∑ ∏ ′ Integrals, derivatives, summation, product and vector operators.
7 Units & Special Symbols ° % ‰ Ω № § SI prefixes, degree, percent, ohm, copyright and more.
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