Shiur (Hebrew: שעור, pronounced "shee-ur", pl. shiurim, שעורים) has two meanings in contemporary Jewish practice. In its definition as a "lesson", a shiur refers to a Torah lecture. In its definition as a "measurement", a shiur refers to the minimum volume of solids or liquids one must consume to fulfill a mitzvah according to halakha (such as the amount of matzah or wine one must consume to fulfill the mitzvot of the Passover… (
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