A tie tack, a pin or stud used to secure a tie to the shirt.(noun)
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Use "tiepin" in a sentence
"He tied the confounded Windsor knot, struggled with his cuff links, and noted that his tiepin, which was a silver spaceship, was upside down."
"Lali allso nawt kno wy she tiepin in furst purrson!"
"Gifts were a Totoro tiepin I'd admired at the Ghibli Museum store, a pair of slippers, DVDs of the Jeremy Brett Sherlock Holmes series and Young Indiana Jones, and the Settlers of Catan board game."