Which term is NOT classified as an infraction in the sport of squash?

Within squash regulations, three terms designate infractions: "Let" (when interference occurs without intentional misconduct, resulting in a replayed rally with no points awarded), "Stroke" (when a player's opponent impedes their shot capability, resulting in point award), and "No Let" (when intentional obstruction occurs, with the point awarded to the obstructed player). "Serve" simply refers to the opening shot that initiates each rally and is not an infraction term.