One of the few Hebrew words that most English speakers know is "kosher". When used to describe food, it means that it conforms to the regulations of Jewish dietary laws, and in the more general sense it can mean "legitimate, genuine, correct." The word kosher clearly comes from the Hebrew כשר kasher (the pronunciation and spelling kosher is from the Ashkenazic and Yiddish influence), but the Hebrew kasher and its associated words have many more meanings. Let's take a look.
As I've discussed before, I listen to a lot of podcasts. However, in that previous post I didn't mention one podcast that would be of particular interest to readers of Balashon. In each episode of the podcast StreetWise Hebrew, host Guy Sharett takes a Hebrew root, and shows its various forms and uses in Modern Hebrew, accompanied by clips from news broadcasts, commercials, songs and more. Each podcast is only 10-15 minutes, and it's great for both those learning Hebrew for the first time, as well as more veteran fans of the language (like me). I highly recommend it.
In his episode on the word kasher, Guy discusses many words that are related to that root. In addition to kasher - which, similar to "kosher" in English, also means "fit, valid, reliable" (besides its association with food), he also provides the following words:
kashir – Capable – כשירYou should notice that all the words listed have something to do with either being fit, or preparing to make fit. Only a few of them have to do with food - and those that do are related to the preparation of the food, not the supervision. If you understand this, the term "kosher salt" will make more sense - it's not that this kind of salt is permitted according to Jewish law (all salt is), but that it is used in the preparation of meat, according to Jewish law.
kishurim – Qualifications – כישורים
hechsher – “Kosherizing,” authorization – הכשר
hachshara – “Kosherizing” meat; training – הכשרה
lehachshir – To render something kosher, to train, to prepare, to authorize – להכשיר
muchshar, muchesheret – Talented – מוכשר, מוכשרת
kosher – Fitness, ability, capability – כושר
Another interesting point here is that Hebrew also has the word "kosher", but it refers to physical fitness, not food you can eat. Probably a healthier approach...
One thing that Guy does not usually discuss is etymology. So let's look at the background to this root.
The root only appears a few times in the Tanach, mostly in the later books. Esther (8:5) has the adjective kasher, and Kohelet has the verb form twice (10:10, 11:6) as well as the related kisharon כשרון - "talent, skill" (2:21, 4:4, 5:10). The appearance in these books is generally attributed to an Aramaic influence where the word is commonly used, and Klein finds cognates in the Ugaritic ktr (=fit, suitable) and Akkadian kasharu (= to succeed).
Two other biblical words, which each appear only once in the Tanach, and may be related to the root are kosharot כושרות in Tehillim 68:7 whose meaning is unclear, and might mean "prosperity" (although the Radak and other say it might derive from the root קשר - "to bind"), and kishor כישור - "distaff " in Mishlei 31:19. Klein says that the etymology of kishor is uncertain, and the BDB suggests that perhaps the origin is in the root ישר - "to make straight".
Yaakov Etzion discusses the etymology of the root further in this post. He points out that kasher is used often in the Aramaic targumim of the Hebrew Tanach as a translation of yashar ישר - "right, just", and is found - in various forms - very frequently in Rabbinic Hebrew (which had much influence from Aramaic).
He focuses on the interesting word machshir מכשיר - which in Modern Hebrew means "tool, device, instrument". Guy didn't discuss it in his podcast. How is it related to the senses of "preparation" or "fitness"?
Jastrow defines the term as it appears in Talmudic Hebrew as "preparatory means, preliminary acts", and the eponymous tractate of Mishna meant "things which make an object fit for levitical uncleanness". (Etzion points out that we see from these examples and other similar ones that the root kasher is not always used to mean something prepared for a positive use).
As Hebrew began its renewal as a spoken language, machshir was adopted in a number of compound phrases (much more common in that period than now), but still maintaining the sense of things that are "preparatory". So Etzion gives the examples of machshirei seuda מכשירי סעודה as "things needed to prepare a meal" (like a tablecloth and silverware) and machshirei ketiva מכשירי כתיבה - "things needed for writing" (like pen and paper). But over time the sense of "preparatory, necessary" was dropped and it just became a word for tool, instrument (a synonym for keli כלי). So for example, machshirei chashmal מכשירי חשמל are electric devices, with no sense of "preparation" for electricity.
So I hope I've prepared you to use the root kasher properly. And now I need to go for a walk, listen to my podcasts, burn off all this kosher food I just ate, and get into kosher!