What is "Glatt?"

Kosher meat products regularly bear the OU symbol with the word “Glatt.” What does this mean, and would the product still be kosher if it isn’t Glatt?

The Talmud (Chullin 42a) delineates a number of physical defects that an animal may have which would render it treif. The most common of these is a punctured lung. Additionally, lungs often have adhesions which could indicate that there is a rupture in the lung, or it could lead to the development of one. Because of the prevalence of this defect, the Talmud mandates that every lung be checked for abnormalities (Rashba Chullin 9a). There are many types of adhesions, and each must be tested and evaluated before the animal can be declared kosher. The type of tests to be carried out are a subject of debate between the Shulchan Aruch and the Rama (Y.D. 39:13). While the Rama does record some customary leniencies that the Shulchan Aruch disapproves of, Rama himself expresses some hesitation in the prevailing custom to be lenient.

Meat of an animal which is found not to have adhesions which require these questionable assessments is called “Glatt” – Yiddish for smooth, an indication to the condition of the lung. Others, which have been subjected to these assessments, are called “Kosher”.

Because of Rama’s hesitation, and in order to satisfy glatt kosher consumers, the OU only certifies Glatt Kosher meat.


The Gerald & Karin Feldhamer OU Kosher Halacha Yomis is dedicated to the memory of Rav Yisroel Belsky, zt"l, who served as halachic consultant for OU Kosher for more than 28 years; many of the responses in Halacha Yomis are based on the rulings of Rabbi Belsky. Subscribe to the Halacha Yomis daily email here.