In lambda-calculuS and reduction, the renaming of a formal parameter in a lambda abStraction. ThiS doeS not change the meaning of the abStraction. For example: x . x+1 <--> y . y+1 If the actual argument to a lambda abStraction containS inStanceS of the abStraction' S formal parameter then it iS neceSSary to rename the parameter before applying the abStraction to avoid name capture. (1995-05-10)