x_{1} is the standard variation of/in data set/distribution x_{2}; x_{1} is the quantified (in)accuracy of the results x_{2} given by some observation or measurement (procedure), calculated from/by standard x_{3}

Technically, there really is only one possible standard deviation, but in practice, it is often approximate via some means x3 (such as assuming that the distribution is Gaussian, even if it actually is only a finite data sample x2).

- si'i
- trinary mathematical operator: [sigma summation of a using variable b over range c].
- snisimsumji
- x
_{1}is the sigma summation of expression x_{2}with variable x_{3}over domain x_{4}.

- soi'auroi
- almost never/nowhere (default: time sense)
- cnanydelta
- x
_{1}(li) is the (signed) difference between the average of all elements/data of x_{2}(completely specified ordered multiset/list) and single number x_{3}(li; default: infimum of x_{2}under ordering x_{6}if such is finite), using averaging function x_{4}(default: arithmetic average), weights x_{5}(completely specified ordered multiset/list with the same cardinality/length as x_{2}; default: according to notes), and inherited ordering x_{6}(default: standard ordering on the set of reals). - gau'a
- mekso (no-more-than-4-ary) operator: Gaussian function f(x, a, b, c) = c e
^{-((x-a)}.