🔼The name Enaim in the Bible
It appears to be somewhat contested whether Enaim (or Enayim) is a Biblical name or else an ordinary, albeit unusual word. The translators of the Vulgate saw it as not a name and those of the King James and the older Dutch and German translations did the same, and translated Enaim into regular text (ranging from "and open place" to "entrance of two fountains" or "place where two ways meet"). The modern versions of the Bible all seem to have abandoned this tradition and now speak of a place named Enaim.
And it was there, at Enaim, that Tamar sat and awaited Judah to trick him into impregnating her. She was originally the wife of Judah's first son Er, but he died leaving Tamar childless. Since that was back then even worse than it is now, Judah commanded his second son Onan to have relations with Tamar and give her children (and this according to the Levirate law). But, after being famously obstinate about the whole affair, Onan died as well. And so Judah promised Tamar to son number three, named Shelah, who was then only a child.
But by the time Shelah had grown up, the promise to Tamar was pretty much forgotten about, and Tamar dressed up like a prostitute and managed to entice Judah himself to have a go at her. She conceived and had cleverly also secured ways to prove that Judah was the father. If she hadn't, she would have been executed, but now that she had, she gave birth to her twin sons Perez and Zerah and probably lived happily and safely ever after.
Most scholars declare that Enaim is probably the same as Enam, which was also situated in Judah, but that's conjecture and by no means certain.
🔼Etymology of the name Enaim
The name Enaim is a proper dual form of the noun עין (ayin), meaning eye or fountain:
The name Enaim literally means (Two) Fountains or (Two) Eyes. Yet for a meaning of the name Enaim, NOBSE Study Bible Name List reads a curious Place Of A Fountain. Jones' Dictionary of Old Testament Proper Names is old-school and doesn't treat the name Enaim (but briefly mentions it under Enam). BDB Theological Dictionary (usually also old-school), declares Enaim to be the same as Enam, but doesn't translate either name.