Hunting oscillation is a self-oscillation, usually unwanted, about an equilibrium.[1] The expression came into use in the 19th century and describes how a system "hunts" for equilibrium.[1] The expression is used to describe phenomena in such diverse fields as electronics, aviation, biology, and railway engineering.[1]
f. The action of a machine, instrument, system, etc., that is hunting (see hunt v. 7b); an undesirable oscillation about an equilibrium speed, position, or state.