Bound variable

A bound variable is a variable in a logical or mathematical expression that is linked to a specific quantifier, such as "for all" (∀) or "there exists" (∃). When a variable is bound, its meaning is limited to the scope of that quantifier, meaning it only applies within a particular part of the statement. For example, in "For all x, x is greater than 2," the variable x is bound by the universal quantifier and only has significance within that statement. Bound variables help specify the range or domain of variables in formal logic.