🔼The name Zereth-shahar in the Bible
The name Zereth-shahar occurs only once in the Bible. It's mentioned as one of the cities of Reuben, east of the Jordan (Joshua 13:19). This city is actually called Zereth-hashahar, but for some reason all translations ignore the letter ה (he) in front of the shahar-part.
🔼Etymology of the name Zereth-shahar
The name Zereth-shahar obviously consists of two (of three) elements. The first part is the same as the name Zereth, which is of unclear origin. Some scholars take it from the root צהר:
Others note that the name Zereth is identical to the word צרת (zeret), meaning distress:
The second part of our name comes from either of the two verbs שחר (shahar):
The letter ה (he) in front of the shahar-part is either the definite article, or it declares a motion towards whatever the shahar-part is supposed to mean.
The name Zereth-shahar can mean a lot of things and it's ultimately unclear what the original name-giver had in mind. NOBSE Study Bible Name List takes the first part from צהר and interprets that root with being bright. Hence NOBSE translates our name with The Splendor Of Dawn. At first glance this seems a pretty consistent phrase but it's highly unlikely that anyone who would want to captivate the brilliance of a sunrise would choose these words. It seems more likely that a Hebrew audience would interpret this name as Distress Of Darkness or even (The God) Shahar Binds.
Jones' Dictionary of Old Testament Proper Names and BDB Theological Dictionary don't offer any interpretation of this name.