🔼The name Sur in the Bible
The name Sur occurs only once in the Bible. Apparently it's the name of a gate associated with Solomon's temple complex. Where that gate was situated precisely isn't clear, but when high priest Jehoiada plotted to overthrow the crazy queen mother Athaliah by installing young prince Joash on the throne, he instructed one third of the available Carites and guards to stay posted at the Gate Sur (שער סור, sha'ar sur), and keep watch over the temple (2 Kings 11:6).
The Chronicles tells the same story but speaks of שער היסוד (sha'ar hayeshod), which means Gate of the Foundation (2 Chronicles 23:5). Note that the words יסוד (yeshod) and סור (sur) look suspiciously similar (because the letters ד, d, and ר, r, would seem similar to a neophyte), and some scholars believe this duality is due to a scribal error. Other scholars find this suggestion rather absurd and suspect that the Chronicler used this and other subtle changes to an end that is still unclear to us.
Why the various versions of the translated Bible print a transliterated Gate of Sur in 2 Kings 11:6 but a translated Gate of the Foundation in 2 Chronicles 23:5 is also a mystery.
🔼Etymology of the name Sur
The name Sur probably comes from the verb סור (sur), meaning to turn aside:
For a meaning of the name Sur, NOBSE Study Bible Name List reads Turning Aside, Entrance, but where "Entrance"-part comes from isn't clear. It's certainly not implied by the name.
Jones' Dictionary of Old Testament Proper Names proposes Go Back, and explains that this gate might have signified the point of no return; a visitor had to make sure he was ritually clean because once past the Gate Of Going Back, his impurities would go straight to his rap sheet. This creative interpretation is a guess, of course, and we might as well guess that this gate signified a turning away from one's daily routine to spend some quiet time with the Lord. We simply don't know.
BDB Theological Dictionary does not offer an interpretation of this name but does list it under the verb סור (sur), meaning to turn aside.