tie tack
tiepin
scarfpin

His tie tack caught the overhead lights.

Each policeman had a cross-shaped tie tack.

Harvey looked it over; and then he aimed the camera exactly down the middle of the desk, and he put the pencil right in front of him, in line with his tie tack.

Inside, Allan flipped over his tie tack.

Bosch was fully dressed, right down to a rumpled tie held to his white shirt by a silver 187 tie tack.

The ties come with working tie tacks of cultured pearls or semi-precious stones.

The tie tack was monogrammed.

Most plainclothesmen had a cross-shaped tie tack.

Corporal Quill said the driver tried being friendly by saying: "Nice tie tack.