ADONI-ZEDEK (a-dō'nī-zē'dĕk, Heb. ’ădhōnîtsedheq, lord of righteousness, or, my lord is righteous). Amorite king of Jerusalem (Josh.10.1-Josh.10.27). Having heard how Joshua destroyed Ai and Jericho and how Gibeon made peace with Israel, Adoni-Zedek invited four other Amorite kings to join him in attacking Gibeon. Joshua came to the aid of Gibeon. God defeated the kings, both in battle and with great hailstones. This was the day when Joshua called on the sun and moon to stand still until the people had avenged themselves on their enemies. The kings hid in a cave, which Joshua sealed with great stones. When he had completed the victory, Joshua ordered the kings brought out. He killed them and hanged them on trees until sunset, when they were cut down and buried in the cave where they had hidden. An earlier king of Jerusalem (Salem) bore a name of similar form and identical meaning: Melchizedek, “king of righteousness” (Gen.14.18-Gen.14.20). This may well indicate the continuation of the same dynasty with the same dynastic name; at all events it indicates that even if the dynasty changed, there was some reason why the pre-Davidic kings of Jerusalem thought it important to preserve the same name or title. See also Melchizedek.
International Standard Bible Encyclopedia (1915)
King of Jerusalem at the time of the conquest of Canaan (Jos 10:1). When he heard of the fall of Ai and the submission of the Gibeonites, he entered into a league with four other kings to resist Joshua and Israel, and to punish Gibeon (Jos 10:3,4), but was overthrown by Joshua in a memorable battle (Jos 10:12-14). Adoni-zedek and his four allies were shut up in a cave, while the battle lasted, and afterward were taken out by Joshua’s order, put to death and hanged on trees (Jos 10:22-27). It is noticeable that the name is almost the equivalent of Melchizedek, malkitsedheq, "king of righteousness," who was ruler of Jerusalem in the time of Abraham.
ADONI-ZEDEK (ADONI-ZEDEC) ə dō’ nī ze’ dĕk (אֲדֹֽנִי־צֶ֜דֶק, my lord is righteousness). King of Jerusalem (KJV ADONI-ZEDEC) when the Israelites invaded Canaan under Joshua (Josh 10:1, 3). When he heard of the fall of Ai and the league of the Gibeonites with Israel, he entered into a coalition with four other Amorite kings to the S and W of Jerusalem with the purpose of punishing the city of Gibeon. Joshua and his men quickly came to the assistance of Gibeon. In a memorable battle in which the sun stood still, the confederate forces were badly defeated. The five kings were shut up in a cave in which they had hidden. When the battle ended, they were slain and their bodies were hung up until the evening; when they were removed and sealed in the cave with large stones.