<logic> an alphabet and grammar. The alphabet is a set of uninterpreted symbols. The grammar is a set of rules that determine which strings of symbols from the alphabet will be acceptable (grammatically correct or well-formed) in that language. The grammar may also be conceived as a set of functions taking strings of symbols as input and returning either "yes" or "no" as output. The rules of the grammar are also called formation rules.
See decidable system, finitary formal system, wff
[Glossary of First-Order Logic]
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