Answered by Sayyidi Habib Umar bin Hafiz (may Allah protect him and benefit us by him)
What is the difference between a ‘hizb’ and a ‘ratib’?
They are essentially the same thing. Linguistically a ‘ratib’ is a fixed thing which is recited consistently and a ‘hizb’ is a section or an amount of Qur’an or adhkar which is recited.