Kezayit, k'zayit, or kezayis () is a

Talmud The Talmud (; he, , Talmūḏ) is the central text of Rabbinic Judaism and the primary source of Jewish religious law ('' halakha'') and Jewish theology. Until the advent of modernity, in nearly all Jewish communities, the Talmud was the cen ...

ic unit of volume approximately equal to the size of an average

olive The olive, botanical name ''Olea europaea'', meaning 'European olive' in Latin, is a species of small tree or shrub in the family Oleaceae, found traditionally in the Mediterranean Basin. When in shrub form, it is known as ''Olea europaea'' ...

. The word itself literally means "like an olive." The rabbis differ on the precise definition of the unit: * Rabbeinu Yitzchak (the Ri) defines it as one-half of a beytza (a beytza is the volume of an egg). *

Maimonides Musa ibn Maimon (1138–1204), commonly known as Maimonides (); la, Moses Maimonides and also referred to by the acronym Rambam ( he, רמב״ם), was a Sephardic Jewish philosopher who became one of the most prolific and influential Torah ...

specified that a 'grogeret' (dried fig) was one-third of a beytza, making this the maximum size for a kezayit, which is smaller. Rabbeinu Tam made the argument explicitly, though, using a slightly different calculation came out with a maximum definition of three-tenths. * According to some interpretations, including the Chazon Ish, the ''zayit'' is not related to other units by a fixed ratio, but rather should only be conceived of independently as the size of an average olive. Its uses in

halacha ''Halakha'' (; he, הֲלָכָה, ), also transliterated as ''halacha'', ''halakhah'', and ''halocho'' ( ), is the collective body of Jewish religious laws which is derived from the written and Oral Torah. Halakha is based on biblical comm ...

include: * The minimum amount food that, when eaten, is halachically considered "eating." This has implications throughout the spectrum of halacha, including: ** For prohibitions of consumption, as in the eating of '' milk and meat'' ** For the saying of a Bracha Ahrona (the traditional grace after meals) * People exposed to at least a ''kezayit'' of the flesh of a dead body become ritually impure.

See also