noun
eyeliner
Refers to the cosmetic product or the line drawn along the eyelid. Wasei-eigo from 'eye line'; in English, 'eyeliner' is the standard term.
wasei-eigo (Japanese-coined English), from eye line
今日はアイラインを少し太めに引いてみた。
Today I tried drawing my eyeliner a little thicker.
このアイラインは落ちにくくて気に入って
I like this eyeliner because it doesn't smudge easily.