penknife

名词 penknife:

1. a small pocketknife; originally used to cut quill pens

pen.knife

n.（名词）
A small pocketknife.
一种袖珍折刀

来源：
[So called because it was originally used for cutting quill pens]
[这么称是因为从前它是用来削羽笔的]