Retrusion refers to the act of pulling back or moving backwards. Synonyms for retrusion include retraction, withdrawal, retreat, receding, and fallback. These words may have slightly different connotations depending on the context in which they are used. Retraction often refers to the retraction of a statement or argument, while withdrawal can refer to the physical retraction of a limb or body part. Retreat can refer to a military or strategic withdrawal, whereas receding often describes a gradual withdrawal or fading away. Fallback is often used in the context of contingency plans or backup measures. In any case, all of these words convey a movement or action that is directed backwards.