umukōbwācu (aba-)     1  class 1
singular: umu-
plural: aba-
  
1. daughter of my sister (when girl speaking), 2. daughter of my brother (when boy speaking)
daughter    umukōbwa
(of my, your, his sister if one is girlof my, your, his brother if one is boy) umukōbwācu, umukōbwānyu, umukōbwābo
En-En dictionary 
niece    (daughter of sister, if a girl; daughter of brother, if boy) umukōbwacu, umukōbwanyu, umukōbwabo
(daughter of brother, if one is a girl) umusēngezana
(daughter of one's sister if one is a boy) umwīshwa
En-En dictionary