So, "acoustic" generally refers to things related to sound, especially:
* Sound waves: The way sound travels through the air or other mediums.
* Hearing: The process of perceiving sound.
* Sound production: The creation of sound, whether naturally or through instruments.
Here are some examples of how "acoustic" is used:
* Acoustic guitar: A guitar that produces sound through the vibration of its strings, rather than through electronic amplification.
* Acoustic phonetics: The study of the production and perception of speech sounds.
* Acoustic impedance: A measure of how easily sound waves can travel through a material.
* Acoustic ceiling: A type of ceiling designed to absorb sound and reduce noise levels.