The key word for the subject of the dietary laws, the kashruth. It comes from the Hebrew kasher, meaning ‘to make fit’. In the English language it has acquired a wide meaning and many applications: correct, genuine, authorized, legitimate (in almost any context). In the narrower sense it refers to articles of food which are permitted to Jews and have been prepared in accordance with the dietary laws. It can also be used of a restaurant or a cookery book, and appears in the expression ‘to keep kosher’.