🔼The name Mysia in the Bible
The name Mysia belonged to a region of Anatolia (or Asia Minor, which is modern Turkey), namely the far north-western part that sits straight south of the Bosporus and the Sea of Marmara (which is the smaller body of water in between the Black Sea and the Aegean Sea, towards the Mediterranean).
Mysia was coastal in its north, but in the west it was bordered by the Troad. In Roman times the Troad was absorbed by Mysia, and Mysia itself became part of the province of Asia.
Mysia is mentioned twice in the Bible, but in the same, enigmatic scene in which Jesus and the Holy Spirit forbade Paul, Silas and Timothy to speak the word in either Asia or Bithynia, and the men were forced to journey on to Troas and finally Macedonia in Europe (Acts 16:7 and 16:8).
🔼Etymology of the name Mysia
The name Mysia is very old and it's not clear who and in which language it was first concocted.
In the Iliad, Homer mentioned a land called Mysia, but it's not wholly clear whether he meant the same as the region later known by that name, or whether he was speaking of a proverbially decrepit people.
The word for Mysian, Μυσος (Musos), is the same as the noun μυσος (musos), meaning uncleanness or defilement. Various other poets described the Mysians as "proverbially feeble and effeminate" or "a prey to all" (said of anything that can be plundered with impunity) and even "the most worthless of men" (says Liddell and Scott's A Greek-English Lexicon):
What the Mysians were guilty of to deserve such vile assessment isn't clear, and the name may even have originated merely as a description of the region's diminished accessibility due to several mountains.
The name Mysia probably primarily meant Hidden or Covered, and may even have denoted a school of inquiry. But since the identical word musos came to denote something that people rather wanted to see hidden and covered, the name Mysia became synonymous with Dirt or Defilement.