Where does “emacsen” come from?

emacsen (English) comes from English Emacs, from English editor, from Medieval Latin editor, from Latin ēditor, from Latin ēditus, from Latin edō, from Latin -ilis, from Proto-Italic -elis — Forms agent nouns from verbal roots.

Ancestry of “emacsen”, step by step

StepLanguageWordMeaning
1EnglishEmacsA particular visual or WYSIWYG text editor (first written by Richard Stallman in 1975 but since reimplemented by others in several distinct versions), distinguished by its use of control characters as editing commands, by its lack of distinct "insert" and "edit" modes, and by its featurefulness and
2EnglisheditorA person who edits or makes changes to documents;...
3Medieval Latineditorsecond/third-person singular future passive...
4Latinēditoreditor, publisher
5Latinēditusbrought forth, having been brought forth; ejected, having been ejected, discharged, having been discharged
6Latinedōto eat
7Latin-ilis-ile
8Proto-Italic-elis
9Proto-Indo-European-elis
10Proto-Indo-European-lósForms agent nouns from verbal roots
Every word from Proto-Indo-European -lós