Kasher ( ):

By: Kaufmann Kohler , Julius H. Greenstone

Original meaning, "fit," "proper" (as in Esth. viii. 5; Eccl. x. 10, xi. 6); later, in rabbinical literature, it took the meaning of "fit," "permitted," in contradistinction to "pasul" and "terefah" (="unfit," "forbidden"), Extensively used in the Halakah, the word crept into the common parlance of the Jews, and the verb "kasheren" was formed to denote any process by which food or vessels for food are made ritually fit for use. Thus the process of cleansing vessels used for the Passover festival ( see Leaven ) is known by that term; also the process of immersing in a ritual bath new metal vessels bought from a non-Jew ( see Purity ). "Kasheren" is especially applied to the ritual preparation of meat. In order to soften meat before it is salted, so as to allow the salt to extract the blood more freely, the meat is soaked in water for about half an hour. It is then covered with salt for about an hour, and afterward washed three times (Shulḥan 'Aruk, Yoreh De'ah, 69; see Meliḥah ). This whole process is designated by the term "kasheren." See also Dietary Laws .