Usually it is uses of words, not words in themselves, that are properly called vague.

About J. L. Austin

John Langshaw Austin, OBE, FBAwas a British philosopher of language and leading proponent of ordinary language philosophy, best known for developing the theory of speech acts.
Austin pointed out that we use language to do things as well as to assert things, and that the utterance of a statement like “I promise to do so-and-so” is best understood as doing something–making a promise–rather than making an assertion about anything.

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