Толковый словарь английского языка - norm

noun Etymology: Latin ~a, literally, carpenter's square Date: 1674 an authoritative standard ; model, a principle of right action binding upon the members of a group and serving to guide, control, or regulate proper and acceptable behavior, average: as, a set standard of development or achievement usually derived from the average or median achievement of a large group, a pattern or trait taken to be typical in the behavior of a social group, a widespread or usual practice, procedure, or custom ; rule , 4. a real-valued nonnegative function defined on a vector space with value analagous to length and satisfying the conditions that the function is zero if and only if the vector is zero, the function of the product of a scalar and a vector is equal to the product of the absolute value of the scalar and the function of the vector, and the function of the sum of two vectors is less than or equal to the sum of the functions of the two vectors, the greatest distance between two successive points of a set of points that partition an interval into smaller intervals, see: average