Engineering notation reference

Engineering Symbols Reference

Search and copy common engineering symbols, Greek letters, math operators, units, and notation used in equations, reports, drawings, and calculations.

Searchable reference

Copy engineering symbols and notation

Filter the table by symbol, name, command, unit, drawing term, or engineering use case.

Symbols

Best for

Reports and equations

Copy symbols for stress, density, viscosity, angles, diameter, temperature, and mathematical notation.

Watch out

Define every symbol

The same symbol can mean different things depending on field, equation, and unit system.

Reference table

Common engineering symbols and meanings

Category	Name	Common engineering use
Greek	alpha	Angle, coefficient, thermal diffusivity
Greek	beta	Coefficient, angle, beta factor
Greek	gamma	Specific weight, shear strain
Greek	delta / change	Finite change or difference
Greek	epsilon	Strain, emissivity, permittivity
Greek	theta	Angle or angular position
Greek	lambda	Wavelength, eigenvalue, slenderness
Greek	mu	Dynamic viscosity, coefficient of friction, micro prefix
Greek	nu	Poisson ratio, kinematic viscosity
Greek	pi	Circle constant
Greek	rho	Density
Greek	sigma	Normal stress, standard deviation
Greek	tau	Shear stress, time constant
Greek	phi	Angle, phase, potential
Greek	omega	Angular velocity
Math	approximately equal	Rounded or approximate values
Math	plus-minus	Tolerance or uncertainty
Math	less than or equal	Limits and constraints
Math	greater than or equal	Limits and constraints
Math	square root	Root expressions
Math	summation	Series and totals
Math	integral	Calculus and continuous sums
Technical	degree	Angles and temperatures
Technical	diameter	Hole and shaft diameters
Technical	micro	Metric prefix, micrometer
Technical	infinity	Limits, asymptotes, idealized values

How to use

Practical notation checks

Copy carefully

symbol + meaning + units

A symbol is only useful when its meaning and units are clear in the surrounding equation or drawing note.

Avoid ambiguity

same symbol, different fields

Symbols such as E, G, R, and sigma can mean different things in different engineering domains.

Match the standard

notation follows context

Use notation that matches the drawing, report, coding, or calculation standard used by your team.

Search first

name, symbol, command, or unit

Use the search field to jump directly to the needed symbol, constant, or notation.

Definitions

Key notation concepts

Greek letters

Common symbols for engineering variables such as stress, density, viscosity, angle, and efficiency.

Operators

Mathematical symbols used to describe equality, approximation, change, summation, roots, and relationships.

Technical symbols

Drawing and documentation symbols such as diameter, degree, plus-minus, and micro.

Unicode

Character encoding that lets symbols be copied into documents, spreadsheets, and web pages.

FAQ