名詞 fastener:

1. a person who fastens or makes fast
2. restraint that attaches to something or holds something in place
   同義詞：fastening, holdfast, fixing

1. A slim, pointed piece of metal hammered into material as a fastener.
   釘子，圖釘一細的尖頭金屬，用于楔入某物，如圖釘
2. He's nipped his thumb in the fastener.
   他的姆指被鉤扣夾住了。