Ec
- Eccentric
- A circle not having a geometric centre.
- Eccentricity
- The variation of the outer diameter of a shaft surface when referenced to
the true geometric centreline of the shaft.
- Eccentricity of Loading
- Distance between the actual line of action of compressive or tensile loads and the line of action that would produce a uniform stress over the cross section of the specimen.
- Eccentricity Ratio
- The vector difference between the bearing centreline and the average steady-state journal centreline.
- ECCM
- Abbreviation of Electronic Counter-Countermeasures.
- Echo
- A delayed return of sound that is perceived by the ear as a discrete sound image.
- Echo Location
- Determining the location of a target relative to the sensor face by means of measuring the time it takes for a sound wave to travel to the target and be reflected back to the sensor
- Echo Sounding
- Measurement of the depth of the ocean by directing a sonic or ultrasonic pressure wave vertically downward and determining the time taken before the echo is received.
- Echograms
- A record of the very early reverberatory decay of sound in a room.
- Eclipse
- A chance alignment between the Sun and two other celestial objects within the
solar system in which one body blocks the light of the Sun from the other.
- ECM
- Abbreviation of Electronic Countermeasures.
- Ecology
- The study of living things in their environment.
- Ecosystem
- A community of living things together with their environment.
- ECU
- Abbreviation of Electronic Control Unit.