Achish

Achish - Probably meaning "angry," (see below for other theories of its origin and meaning), and perhaps only a general title of royalty applicable to the Philistine kings. Name of two kings of Gath (which is identified by most scholars as Tell es-Safi).(1.) The king with whom David sought refuge when he fled from Saul (1 Sam. 21:10-15). He is called Abimelech (meaning "father of the king") in the superscription of Ps. 34. It was probably this same king, or his son with the same name, to whom David a second time repaired at the head of a band of 600 warriors. The king assigned David to 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.
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(angry), a Philistine king of Gath, who in the title of the 34th Psalm is called Abimelech. David twice found a refuge with him when he fled from Saul. (B.C. 1061.) On the first occasion he was alarmed for his safety, feigned madness, and was sent away.
  

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).