Johann Gottfried Müthel
![Johann Gottfried Müthel.](https://upload.wikimedia.org/wikipedia/commons/0/0e/Muethel2.jpg)
As far as is known, he was the first to use the term fortepiano in a published work, in the title of his ''Duetto für 2 Clavier, 2 Flügel, oder 2 Fortepiano'' (1771), which reflects the rising popularity of the instrument at that time. Provided by Wikipedia
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