spirit / soul / divine spirit
Feminine/masculine noun. Plural: أَرْوَاحٌ (arwāḥ). Also refers to Angel Jibrīl: رُوحُ الْقُدُسِ (the Holy Spirit). Related: رَاحَةٌ (comfort).
The Quran maintains mystery about the rūḥ - it is from God's command. This humility before the unknown is itself a Quranic teaching.