Definitions

1. noun

a small ornament, typically made of metal or enamel, worn on a woman’s dress or jacket, especially to hold a brooch or a badge in place

“She pinned a small breastpin to her lapel for the wedding.”

2. verb

to fasten or secure something, especially a brooch or badge, to a woman’s clothing using a breastpin

“She breastpinned the medal to her jacket for the awards ceremony.”