A pasigraphy (from Greek pasi 'to all' and graph 'write') is a writing system where each written symbol represents a concept (rather than a word or sound or series of sounds in a spoken language). The aim (as with ordinary numerals 1, 2, 3, etc.) is to be intelligible to persons of all languages. The term was first applied to a system proposed in 1796, though a number of pasigraphies had been devised prior to that.
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Given the length and nature of the Voynich Manuscript pasigraphy is probably not applicable for the most part.