RASÛL - رسول
A Prophet. A Messenger, who is sent by Allah with a new book and Sharî’ah to an ummah or all humanity. If a Prophet follows the book and the Sharî’ah of a former Rasûl, without having the new ones, he is called a Nabi.
“That Ustadh is both the ‘abd; in point of ‘ubûdiyyah he describes and makes known his Rabb; so he is the envoy of his ummah at the Court of Janâb-i Haqq. He is also a Rasûl, in point of messengership he conveys (tablîgh) his Rabb’s decree to men and the jinn by means of the Qur’an.” The Eleventh Word-First Group