Common is נפוץ. I don't think they are interchangeable in English either.
Can you also translate רגיל as regular? Although I probably wouldn't say, "this is regular. " (I would say, "this is usual," or "this is normal.")
That's one of the meanings the root ר-ג-ל has. For example, להתרגל (in binyan Hitpa'el) means 'to get accustomed to-'.
It's not related to English, since it already appears in the Mishnah. My guess that it's not related to Latin either, just an extension of the known Semitic root ר-ג-ל.
OK, thanks. Then, is there any possibility that Latin got it from Hebrew or some other Semitic language?