What is the Greek or Latin root word for city of brotherly love?

The phrase "city of brotherly love" comes from the Latin phrase "Philadelphia".

* Phil (Greek: φίλος) means "love" or "friend".

* Adelphos (Greek: ἀδελφός) means "brother".

Therefore, Philadelphia literally means "brotherly love". It is the name of a city in Pennsylvania, USA, and also a city in Mississippi, USA.