The descending wedge symbol ∨ may represent:
Logical disjunction in propositional logic Join in lattice theory The wedge sum in topology The V sign, a symbol representing peace among other things
The vertically reflected symbol, ∧, is a wedge, and often denotes a related or dual operator.
The ∨ symbol was introduced by Russell and Whitehead in Principia Mathematica, where they called it the Logical Sum or Disjunctive Function.
In Unicode the symbol is encoded . In TeX, it is \vee or \lor.
One motivation and the most probable explanation for the choice of the symbol ∨ is the latin word "vel" meaning "or" in the inclusive sense. Several authors use "vel" as name of the "or" function.
References
See also List of mathematical symbols List of logic symbols