PURTENANCE pûr’ tə nəns (קֶ֫רֶב, H7931, within, inward). An archaic word meaning the viscera of an animal. It refers to the “inwards” of the passover lamb (Exod 12:9, KJV, ASV). RSV has “its inner parts.”

International Standard Bible Encyclopedia (1915)

pur’-te-nans: With the significance of "belongings," this word occurs in the King James Version of Ex 12:9 as the translation of qerebh, "within" "inward," "roast .... with the purtenance thereof," the Revised Version (British and American) "inwards" (compare Le 1:9; 3:3, etc.).