🔼The name Helem in the Bible
There are two different Hebrew names in the Bible that in translations appear as the same name Helem. We'll call them Helem I (הלם) and Helem II (הלם), although it may very well be that Helem II (הלם) is not a name at all:
🔼The name Helem I in the Bible
The name Helem, spelled with the letter ה (he), occurs only once in the Bible. Helem of Asher is mentioned as the brother of probably Shemer ("his brother", 1 Chronicles 7:34-35), but it's not clear how they fit in. Two verses prior we read about the sons of Heber, two of whom are named Shomer and Hotham, and some scholars assume that Shomer and Hotham are the same as Shemer and Helem, but there's no proof for this either way.
🔼Etymology of the name Helem I
The name Helem I comes from the verb הלם (halam), meaning to hammer:
🔼Helem I meaning
For a meaning of the name Helem I, Jones' Dictionary of Old Testament Proper Names reads Hammerer. BDB Theological Dictionary does not translate this name but does list it under the verb הלם (halam), meaning to hammer. NOBSE Study Bible Name List doesn't acknowledge a difference between Helem I and II and reads Strength for both (which is incorrect).
Other Biblical names that have to do with a hammer are Mark and Maccabee.
🔼The name Helem II in the Bible
It's not clear whether the name Helem II (spelled with the letter ח, heth) is a name or not. It occurs only once, in Zechariah 6:14, where the crown of Joshua is said to be a memorial in the temple of YHWH to Helem, and to Tobijah, and to Jedaiah, and to Hen son of Zephaniah. The odd thing is that in 6:10, YHWH orders Zechariah to collect a contribution from Heldai, and from Tobijah and from Jedaiah to make the crown. The names Hen and Helem II occur nowhere else in the Bible, which is odd enough to begin with, but why would Tobijah and Jedaiah get to pay for the crown and then also enjoy its use in the temple, while Heldai pays but won't enjoy and Helem and Hen don't pay but do enjoy?
To make matters even more complicated: Zechariah wrote in the late sixth century BC, during a time when the restoration had already long begun and appears to have been as good as finished (Zechariah 4:9). About two and a half centuries later (3rd century BC), Hellenized Jews would compose the Septuagint, and they didn't interpret Heldai, Tobijah, Jedaiah, Helem II and Hen as names but as regular words of the narrative. Six centuries after the Septuagint came Jerome's Vulgate (382-405 AD), and Jerome was the first to impose names on Zechariah 6:9-15 (or at least to print them there). Traditions had obviously diverged but since our modern translations are all either directly based on or otherwise heavily influenced by the Vulgate, modern translations still all endorse the dubious existence of a group of men, of few of whom no other writer mentions.
🔼Etymology of the name Helem II
Whether Helem II is a name or not, it appears to stem from the verb חלם (halam), which either means to be or grow strong, or else to dream:
🔼Helem II meaning
For a meaning of the name Helem II, both BDB Theological Dictionary and NOBSE Study Bible Name List read Strength. Jones' Dictionary of Old Testament Proper Names proposes Robust, but that's taking yet another liberty with the text. Robustness is not implied by either verb חלם (halam).
The Septuagint prints instead of the name Helem, an expression of the verb υπομενω (hupomeno), meaning to persevere (as used in Matthew 10:22, Romans 12:12, Hebrews 10:32), and reads for Zechariah 6:14: "The crown shall be for endurance, and for availment, and for insight, and for the grace of the son of Zephaniah," which seems to make more sense than the modern translations.