Where does “بحر الروم” come from?

بحر الروم (Arabic) comes from Arabic رُوم, from Middle Persian 𐭧𐭫𐭥𐭬, from Ancient Greek Ῥωμανία, from Ancient Greek -ῐ́ᾱ, from Proto-Indo-European -íh₂, from Proto-Indo-European -h₂ — Creates collective nouns, which refer to groups...

Ancestry of “بحر الروم”, step by step

بحر الروم traces back through two separate lines of ancestry.

via Arabic رُوم

StepLanguageWordMeaning
1ArabicرُومByzantines
2Middle Persian𐭧𐭫𐭥𐭬Rome; Byzantine
3Ancient GreekῬωμανίαByzantine Empire
4Ancient Greek-ῐ́ᾱ{{l|en|-ia}}; "suffix forming abstract feminine...
5Proto-Indo-European-íh₂
6Proto-Indo-European-h₂Creates collective nouns, which refer to groups...

via Arabic بَحْر

StepLanguageWordMeaning
1Arabicبَحْرlittle sea; sea
Every word from Proto-Indo-European -h₂Every word from Ancient Greek -ῐ́ᾱEvery word from Ancient Greek Ῥωμανία