oeil de boeuf oeil de boeuf /ˌwæj də ˈbuːf/

noun

1. A circular or oval window; 17th or 18th century French architecture  ( oeil de boeuf )
   a circular or oval window; 17th or 18th century French architecture
    The grand mansion had an oeil de boeuf that brought in beautiful natural light.
   The grand mansion had an oeil de boeuf that brought in beautiful natural light.