The 'Un is commonly used at the end of ancient elf words to represent all of something. In the case of Fyr'Un, that would be 'All of Life.' Many languages were derived from Druzaic and their meanings and word usage often have similarities with that language of pure magic.
The Sul'Dal had a language derived from both ancient elf and Druzaic. That language did not die with the Sul'Dal but rather, can be found in many of the lawful regions of Elixia, The Plane of Health or Life.
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