1. [theorem proving] A language in which proofs are manipulated and tactics are programmed, as opposed to the logic itself (the "object language"). The first ML was the metalanguage for the Edinburgh LCF proof assistant.
2. [logic] A language in which to discuss the truth of statements in another language.
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Nearby terms: metainformation « Meta-IV « METAL « metalanguage » Metal Oxide Semiconductor » Metal Oxide Semiconductor Field Effect Transistor » metaphone