IPA: /ˈpʌʃˌpɪn/
KK: /ˈpʊʃˌpɪn/
A small pin with a large head that can be easily pushed into a surface, like a wall or bulletin board, to hold papers or notes in place.
She used a pushpin to attach the flyer to the corkboard.
Pushpin → The word is formed from "push" (from Middle English *pushen*, meaning to thrust or shove) and "pin" (from Old English *pinn*, meaning a small pointed object). The term "pushpin" refers to a small pointed object that is used to thrust or shove into a surface to hold something in place.
Think of 'thrusting' something ('push') with a 'small pointed object' ('pin') to hold it in place — that's what a pushpin does.
No commonly confused words.