Food that is not in accord with Jewish law is called treif, (Yiddish: טרייף or treyf, derived from Hebrew: טְרֵפָה trēfáh). In the technical sense, treif means "torn" and refers to meat which comes from an animal containing a defect that renders it unfit for slaughter. An animal that died through means other than ritual slaughter (or by a botched slaughter) is called a neveila which literally means "an unclean thing". 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.