משנה על ביכורים 1:3

The olive of which they spoke it is one that is neither big nor small but of moderate size the egori. The barleycorn of which they spoke it is one that is neither big nor small but of moderate size the midbarit The lentil of which they spoke it is one that is neither big nor small but of moderate size--the egyptian kind. "Any movable object conveys uncleanness if it is of the thickness of an ox goad" it is one that is neither big nor small but of moderate size. What is meant by "one of moderate size?" One whose circumference is just a handbreadth.