Electronics .

the process of returning part of the output of a circuit, system, or device to the input, either to oppose the input (negative feedback) or to aid the input (positive feedback).

acoustic feedback.

the furnishing of data concerning the operation or output of a machine to an automatic control device or to the machine itself, so that subsequent or ongoing operations of the machine can be altered or corrected.

a reaction or response to a particular process or activity

He got very little feedback from his speech.

evaluative information derived from such a reaction or response

to study the feedback from an audience survey.

Psychology . knowledge of the results of any behavior, considered as influencing or modifying further performance. Compare biofeedback .

Biology . a self-regulatory biological system, as in the synthesis of some hormones, in which the output or response affects the input, either positively or negatively.

noun

answer , assessment , comeback , comment , criticism , evaluation , observation , reaction , rebuttal , reply , retaliation , sentiment