Dung - Vine's Expository Dictionary of New Testament Words
Dung[ 1,,G4657, skubalon ]
denotes refuse," whether
(a) "excrement," that which is cast out from the body, or
(b) "the leavings of a feast," that which is thrown away from the table. Some have derived it from kusibalon (with metathesis of k and s), "thrown to dogs;" others connect it with a root meaning "shred." Judaizers counted gentile Christians as dogs, while they themselves were seated at God's banquet. The Apostle, reversing the image, counts the Judaistic ordinances as refuse upon which their advocates feed, Philippians 3:8.
[ 2,,G2874, koprion ]
"manure," Luke 13:8, used in the plural with ballo, "to throw," is translated by the verb "to dung." Some mss. have the accusative case of the noun kopria, "a dunghill." See below.