olemus
kontekstist sõltuv
vabalt valitav aluselement

Wiktionary:
6. (computing) an element of a set to be sorted that is chosen as a midpoint, so as to divide the other elements into two groups to be dealt with recursively
8. (graphical user interface) any of a row of captioned elements used to navigate to subpages, rather like tabs
9. (mathematics) an element of a matrix that is used as a focus for row operations, such as dividing the row by the pivot, or adding multiples of the row to other rows making all other values in the pivot column 0

näiteid
kiirsortimise algoritmis Quicksort:
https://www.cp.eng.chula.ac.th/~vishnu/datastructure/QuickSort.pdf
arvutusalgoritmides:
https://en.wikipedia.org/wiki/Pivot_element