Achish

Achish - angry, perhaps only a general title of royalty applicable to the Philistine kings. (1.) The king with whom David sought refuge when he fled from Saul (1 Sam. 21:10-15). He is called Abimelech in the superscription of Ps. 34. It was probably this same king to whom David a second time repaired at the head of a band of 600 warriors, and who assigned him Ziklag, whence he carried on war against the surrounding tribes (1 Sam. 27:5-12). Achish had great confidence in the valour and fidelity of David (1 Sam. 28:1,2), but at the instigation of his courtiers did not permit him to go up to battle along with the Philistine hosts (1 Sam. 29:2-11). David remained with Achish a year and four months. (2.) Another king of Gath, probably grandson of the foregoing, to whom the two servants of Shimei[?] fled. This led Shimei[?] to go to Gath in pursuit of them, and the consequence was that Solomon put him to death (1 Kings 2:39-46).

From Easton's Bible Dictionary (1897)