A tiepin is a pin that holds a necktie in place. Wear a tiepin, a gold tiepin, a tiepin and cufflinks.
It pushes through the tie and the shirt to keep the tie flat, which a tie clip does by gripping instead. Both fell out of daily use with the suit itself and survive at weddings.
1nountiepinA pin that holds a necktie in place.
“For the wedding, he wore a gold tiepin with a tiny pearl on it.”
tiepin is a pin.
Tie plus pin, from the late nineteenth century, when the modern necktie took its shape.
From tie + pin.
Etymology from Wiktionary, CC BY-SA
Practised in Jewellery & Watches