Answer: thumbtack

AnswerCrossword Clue
THUMBTACKBulletin sticker
THUMBTACKFastening device
THUMBTACKBulletin board fastener
THUMBTACKPushpin
thumbtacka broad-headed tack / to fasten with a thumbtack
thumbtackA short flat-headed pin, used for fastening paper to a wall or other surface