This page provides a reference table of commonly used engineering symbols, their definitions and associated units. These symbols are widely used in mechanical engineering equations, physics calculations and technical drawings.
Understanding engineering nomenclature is essential for interpreting formulae, solving problems and communicating technical information clearly.
| Symbol | Description | Units |
| A | Cross Section Area | m2 |
| a | Acceleration | m/sec2 |
| D | Diameter | m 2 |
| e | Energy | Joule (N.m) |
| e | Strain | - |
| E | Young's Modulus | N/m2 |
| F | Force | N |
| G | Shear Modulus .. Modulus Of Rigity | N/m2 |
| I | Second Moment of Area of a Section about its Neutral Axis | m4 |
| I | Mass Moment of Inertia of a body about its axis of Rotation | kg.m2 |
| J | Polar Moment of Inertia | m4 |
| J | Mass Moment of Inertia of a body about its axis of Rotation | kg.m2 |
| m | Mass | kg |
| M | Moment | N.m |
| p | Tensile/Compressive Stress | N/m2 |
| P | Pressure | N/m2 |
| q | Shear Stress | N/m2 |
| R | Radius | m |
| s | Distance | m |
| t | Time | sec |
| t | Thickness | m |
| T | Torque | N.m |
| v | Velocity | m / s |
| W | Work Done | Joule (N.m) |
| W | Beam Load | N |
| w | Beam Distributed load | N /m |
| x | Distance x direction | m |
| y | Distance y direction | m |
| α | Angular Acceleration | s-2 |
| ε | Shear Strain | Radian |
| θ | Angle | Radian |
| ν | Poisson's Ratio | - |
| π | Circumference/ Diameter | 3.14159 (approx) |
| σ | Stress | N / m2 |
| τ | Shear Stress | N/m2 |
| ω | Angular Velocity | sec-1 |
Engineering symbols are used to represent physical quantities such as force, mass, stress, energy and time. These symbols allow equations to be written in a concise and standardised form across engineering disciplines.
Some of the most frequently used engineering symbols include force (F), mass (m), acceleration (a), stress (σ), strain (ε) and energy (E). These appear in many standard equations used in design and analysis.