wave
Oscillation caused by a disturbance; as it propagates through a medium (mechanical waves) or a vacuum (electromagnetic waves), it carries energy.
mean position
Horizontal line around which the wave oscillates, carrying energy.
wavelength
Distance between two consecutive crests or troughs; it corresponds to the distance traveled by the wave over time (its period).
displacement
Gap in relation to the mean position.
crest
Highest point of the wave.
trough
Lowest point of the wave.
amplitude
Maximum displacement of a wave in relation to its mean position; it corresponds to the amount of energy transmitted.
propagation
Motion of a wave leaving its source.