The German word zettel (Middle and Early New High German zedel, zetel) has the same origin as English schedule (namely medieval Latin schedula, a strip of paper). In Middle High German, it specifically refers to a fixed, written record.
In the German tradition of fencing, most notably in the Liechtenauer school, a zedel is a brief text, usually cast in verse, intended to summarize the art for initiates. A possible English translation of the term is epitome (viz. in the sense of "brief written summary"; so translated by Christian Tobler in 2010).
It is plausible that these epitomes were memorized by students and used as mnemonic devices, but both the term zedel and the deliberate obfuscation of the content (so as to make it impenetrable to uninitiated readers) seem to suggest that they were also intended for written transmission from the beginning. Due to their cryptic nature, most fencing manuals that treat an epitome accompany it with extensive glosses and sometimes even illustrations of the techniques involved.
Specifically used for Liechtenauer's zettel, the term is used in all versions directly associated with the Society of Liechtenauer in the mid-15th century. Its earliest known use is probably in Cod 44A8 (1452), the so-called(?) Pseudo-Peter von Danzig or "Rome version" of the text (fol. 9v):
- Alhÿe hebt sich an dye zedel der Ritterlichen kunst des fechtens dye do geticht vnd gemacht hat Johans Liechtenawer der ain hocher maister In den künsten gewesen ist dem got genadig seÿ
- "Here begin the zedel of the knightly art of combat, which were composed and made by Johannes Liechtenauer, who was an eminent master in these arts, and on whom God may have mercy"
Hans Talhoffer also uses the term in MS Thott.290.2º of 1459 (notably omitting Liechtenauer's name and inserting his own), but does not use it in his earlier 1443 ms. (MS Chart.A.558). Furthermore, the term is used (also without reference to Liechtenauer) in the introduction of MS Best. 720,150 (Hyr hebet sich aen der text vnd zedell ym langen sweerd "Here begins the text and zedel of the long sword").