Boolean

adjective Etymology: George Boole died 1864 English mathematician of, relating to, or being a logical combinatorial system (as Boolean algebra) that represents symbolically relationships (as those implied by the logical operators AND, OR, and NOT) between entities (as sets, propositions, or on-off computer circuit elements)
Example: Boolean expression
Example: Boolean search strategy for information retrieval

Merriam-Webster's Collegiate Dictionary

Boolean

1. Boolean algebra. 2. (bool) The type of an expression with two possible values, "true" and "false". Also, a variable of Boolean type or a function with Boolean arguments or result. The most common Boolean functions are AND, OR and NOT.

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