An artificial international language using characters (as mathematical symbols) instead of words to express ideas

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Pasigraphy \Pa*sig"ra*phy\, n. [Gr. ? for all (dat. pl. of ? all) + -graphy.] A system of universal writing, or a manner of writing that may be understood and used by all nations. --Good.

Wikipedia Word definitions in Wikipedia
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 ...

Wiktionary Word definitions in Wiktionary
n. (context linguistics English) A writing system where concepts are written instead of words. The system is not phonetic and uses ideograms, such as mathematical symbols. It is intended to be universally understood.