| A | B |
|---|
| Larynx | Two folds of tissue that make up the human voice box. |
| Elasticity | The ability of a material to bounce back after being disturbed. |
| Density | Ratio of the mass of a substance to its volume. |
| Intensity | The amount of energy per second carried through a unit area by a wave. |
| Loudness | Perception of the intensity of a sound. |
| Decibel (dB) | A unit of measurement of loudness. |
| Ultrasound | Sound waves with frequencies above 20,000 Hz. |
| Infrasound | Sound waves with frequencies below 20 Hz. |
| Pitch | Perception of the frequency of a sound. |
| Doppler effect | The apparent change in frequency of a sound as the source moves in relation to the listener. |
| Timbre | The overall quality of a sound. |
| Music | A set of tones and overtones combined in ways that are pleasing to the ear. |
| Noise | A mixture of sound waves with no pleasing timbre and no identifiable pitch. |
| Dissonance | The sound produced when notes that have no musical relationship are played together. |
| Acoustics | The study of how well sounds can be heard in a particular room or hall. |
| Beats | The regular changes in loudness of a sound when two sounds of different frequencies are played together. |
| Ear canal | A narrow region leading from the outside of the human ear to the eardrum. |
| Eardrum | A small, tightly stretched, drumlike membrane in the ear. |
| Middle ear | The space behind the eardrum. |
| Cochlea | A fluid-filled cavity behind the inner ear. |
| Sonar | A system of detecting reflected sound waves. |
| Echolocation | The use of reflection of sound waves to navigate and to locate prey. |
| Sonogram | An image formed by an ultrasound machine. |
