The Collaborative International Dictionary of English v.0.48:

Nilotic \Ni*lot"ic\, a. [L. Niloticus, fr. Nilus the Nile, Gr.
   ?: cf. F. nilotique.]
   Of or pertaining to the river Nile; as, the Nilotic
   crocodile.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Nilotic
    adj 1: of or relating to the Nile River or the people living
           near it
    2: of or relating to or constituting the Nilotic group of
       languages; "Nilotic syntax"
    n 1: a group of languages of East Africa belonging to the Chari-
         Nile group [syn: Nilotic, Nilotic language]