The term GRILLE COVER can be solved with the three letter word BRA. A grille cover is a type of protective covering that is placed over a grille, which is an opening in a wall or other structure that allows air to pass through. The grille cover is typically made of metal and is designed to protect the grille from damage while still allowing air to flow freely. A bra is a type of clothing item that is worn by women to provide support and coverage for the breasts. It is usually made of fabric and is designed to be comfortable and supportive.