Dog - Vine's Expository Dictionary of New Testament Words
Dog[ 1,,G2965, kuon ]
is used in two senses,
(a) natural, Matthew 7:6; Luke 16:21; 2 Peter 2:22;
(b) metaphorical, Philippians 3:2; Revelation 22:15, of those whose moral impurity will exclude them from the New Jerusalem. The Jews used the term of Gentiles, under the idea of ceremonial impurity. Among the Greeks it was an epithet of impudence. Lat., canis, and Eng., hound" are etymologically akin to it.
[ 2,,G2952, kunarion ]
a diminutive of No. 1, "a little dog, a puppy," is used in Matthew 15:26-Matthew 15:27; Mark 7:27-Mark 7:28.