catflap.org Online Dictionary Query

  least upper bound
       
           (lub or "join", "supremum") The least upper bound of
          two elements a and b is an upper bound c such that a <= c and
          b <= c and if there is any other upper bound c' then c <= c'.
          The least upper bound of a set S is the smallest b such that
          for all s in S, s <= b.  The lub of mutually comparable
          elements is their maximum but in the presence of incomparable
          elements, if the lub exists, it will be some other element
          greater than all of them.
       
          Lub is the dual to greatest lower bound.
       
          (In LaTeX, "<=" is written as \sqsubseteq, the lub of two
          elements a and b is written a \sqcup b, and the lub of set S
          is written as \bigsqcup S).
       
          (1995-02-03)
       
       

  least upper bound /lˈiːst ˌʌpə bˈaʊnd/ (lub /lˈʌb/)
  Supremum , kleinste obere Schranke  [math.]
           Note: Mengenlehre
     Synonym: supremum
  
   see: suprema
  
           Note: set theory