information about reactions to a product, a person's performance of a task, etc. which is used as a basis for improvement

throughout this process we have obtained valuable feedback

customer feedback suggested that the design flaws were severe

a screeching or humming sound resulting from the return of a fraction of the output signal from an amplifier, microphone, or other device to the input of the same device

Punk Rock Girl opens the disc with plenty of guitar feedback

the modification or control of a process or system by its results or effects, for example in a biochemical pathway or behavioural response