🔼The name Achan in the Bible
There's only one Achan in the Bible, and he's the son of Carmi, son of Zabdi, son of Zerah, son Judah and Tamar. Achan is remembered for having covertly purloined loot — a splendid robe of Shinar and a hardy helping of gold and silver bullion — from the sacked town of Jericho while this was placed under ban by Joshua (Joshua 7:1).
When the men of Ai beat Israel and kill thirty-six men, God tells Joshua that their defeat is due to the presence of banned items in the camp. Lots are cast and Achan's grandfather Zabdi is identified.
Since Achan's grandfather is still living, Achan must have been a young man when he committed this foolish act. But he wasn't too young to have sons, daughters and life stock. Achan and his children are stoned to death and burned in the valley of Achor.
Later, Phinehas the son of Eleazar, refers to the Achan incident and compares it to the Baal-Peor incident while warning the tribes of Reuben, Gad and Manasseh not to deflect (Joshua 22:20). The still later chronicler refuses to even mention Achan by his given name and calls him "Achar (=Troubler), the troubler of Israel who violated the ban" (1 Chronicles 2:7).
🔼Etymology of the name Achan
The name Achan is part of a small group of names that are in the Bible but we don't know where they came from or what they mean. Besides עכן (Achan) in Joshua 7, there's יעכן (Jacan) in 1 Chronicles 5:13, and a town called עכו (Acco) in Judges 1:31. Curiously enough, there is a similar thing going on with the phonetically adjacent names עקן (Akan) and יעקן (Jaakan).
BDB Theological Dictionary briskly declares the meaning of the name Achan unknown. NOBSE Study Bible Name List decides that as Achan is the same person as Achar, the name Achan must also mean the same as the name Achar (Troubler). This isn't true.
Alfred Jones (Jones' Dictionary of Old Testament Proper Names) reports to have found a word in Chaldean that looks a lot like our name Achan, namely עכנא (achana), meaning serpent. Hence Jones reads Serpent.