kosher
Kashrut (also kashruth or kashrus , כַּשְׁרוּת ) refers to Jewish dietary laws. Food in accord with halakha (Jewish law) is termed kosher in English, from the Ashkenazi pronunciation of the Hebrew term kashér (כָּשֵׁר), meaning "fit" (in this context, fit for consumption by Jews according to traditional Jewish law). Jews who keep kashrut may not consume non-kosher food, but there are no restrictions on non-dietary use of non-kosher products, for example, injection of insulin of porcine origin.
Food that is not in accordance with Jewish law is called treif (Yiddish: טרײף or treyf, derived from Hebrew: טְרֵפָה trēfáh ). In the technical sense, treif means "torn" and refers to meat which comes from an animal killed by another animal, killed with a dull knife (so felt pain) or having a defect that renders it unfit for slaughter.
Many of the basic laws of kashrut are derived from the Torah's Books of Leviticus and Deuteronomy, with their details set down in the oral law (the Mishnah and the Talmud) and codified by the Shulchan Aruch and later rabbinical authorities. The Torah does not explicitly state the reason for most kashrut laws, and many varied reasons have been offered for these laws, ranging from philosophical and ritualistic, to practical and hygienic.
Islam has a related but different system, named halal , and both systems have a comparable system of ritual slaughter ( shechita in Judaism and Ḏabīḥah in Islam). Some members of the Seventh-day Adventist Church observe kashrut to a degree.