serif
noun [ C ] publishing specialized /ˈser.ɪf/ uk/ˈser.ɪf/ us/ˈser.ɪf/
（印刷字体的）衬线
a small line that is added to a printed letter in certain typefaces (= particular designs of letters and numbers)
Times New Roman is a popular serif font. Time New Roman是一种流行的衬线字体。
Compare: sans serif