In a preordered set or partially ordered set then the meet or infimum of a subset of elements is, if it exists, the largest element which is smaller or equal to all the elements in the set
If $x$ and $y$ are elements of a poset, then their join, or supremum, is an element $x \vee y $ of the poset such that...
I would like to know the element in common that can 'connect' a meet of a subset with a join of a poset