'Dog' in the Bible

And it is displeasing to Abner exceedingly, because of the words of Ish-Bosheth, and he saith, 'The head of a dog am I -- that in reference to Judah to-day I do kindness with the house of Saul thy father, unto his brethren, and unto his friends, and have not delivered thee into the hand of David -- that thou chargest against me iniquity concerning the woman to-day?

And he bowed himself, and said, What is thy servant, that thou shouldest look upon such a dead dog as I am?

Then said Abishai the son of Zeruiah unto the king, Why should this dead dog curse my lord the king? let me go over, I pray thee, and take off his head.