What does 一筋 mean?
一筋 is a Japanese noun meaning “a single line” or “a streak” in English. It can also be translated as “wholehearted devotion (to one thing)” depending on context. It is written as 一筋 in kanji, ひとすじ in hiragana, and hitosuji in romaji. This word is part of JLPT N1 vocabulary.
Example sentence
涙が一筋頬を流れた。
A tear ran down her cheek.