ballpoint/'bɔːlpɔɪnt $ 'bɑːl-/

n. a pen with a small metal ball at the end that puts ink on the paper

n. [C] 圆珠笔：He took a ballpoint pen out of his pocket. 他从口袋里拿出一支圆珠笔。

◇the words in ballpoint 圆珠笔写的词

构词ball + point

用法“圆珠笔”还可以说ballpoint pen。