supremum

/S UW0 P R IY1 M AH0 M/
noun
  1. 1

    (real analysis): Given a subset X of R, the smallest real number that is ≥ every element of X; : given a subset X of a partially ordered set P (with partial order ≤), the least element y of P such that every element of X is ≤ y.

Source: https://en.wiktionary.org/wiki/supremum