Answer: oeils

AnswerCrossword Clue
OEILS

Trompe l'.. (optical illusions)

OEILS

..-de-boeuf (oval windows)

OEILS... de boeuf: oval windows
OEILS

...-de-chat (cat's-eyes)

OEILS
...-de-boeuf (oval windows)
OEILS
... de boeuf: circular windows