The tradition of giving a family
surname to an individual dates to the colonial period and in most cases the surnames in use today were the second names of the family patriarch of two to four generations ago. Traditionally an individual acquired their father's name after their initiation. Females took on their father's name e.g Cheptoo Kiplagat being the daughter of Kiplagat while males took on just the descriptor portion of the father's name such that the
Kiprono son of Kiplagat would become Kiprono arap Lagat.
Arap (patronym) Arap is
patronym meaning
son of. It was traditionally given following the labetab eun (kelab eun) ceremony and all initiates would after the ceremony acquire their father's name e.g Toroitich son of Kimoi and Kipkirui son of
Kiprotich would after the ceremony be Toroitich arap Moi and Kipkirui arap
Rotich. In modern times it is confined to progressing age-sets independent of the individual initiation ceremony such that if the current age-set is Nyongi, all individuals of preceding age-sets may use the term Arap. ==Nicknames==