IPA: /ˈpaɪliəm/
KK: /ˈpaɪlɪəm/
The upper part of a bird's head, located between the bill and the back of the neck.
The pileum of the sparrow is a distinctive shade of brown.
Pileum → It originates from Latin 'pileum' (meaning a cap or hat). The word refers specifically to a type of head covering.
Think of a 'cap' in Latin — that's what 'pileum' means, a type of hat or head covering.