المؤمن
كلمة (المؤمن) في اللغة اسم فاعل من الفعل (آمَنَ) الذي بمعنى...
It is when a rider allows someone else to ride behind him on his mount.
"Irdaaf" (riding behind someone) is that a rider lets someone else to ride behind him on the same riding animal. "Irdaaf" is fulfilled only when both riders are on the back of one animal at the same time.
"Irdaaf": to let someone ride behind you. It is derived from "ardafa", which means: he let (someone) ride behind him. Original meaning of "ridf": what follows something or what comes after it.
Placing something behind something else.