What does 幹線 mean?
幹線 is a Japanese noun meaning “main line, trunk line” in English. It is written as 幹線 in kanji, かんせん in hiragana, and kansen in romaji. This word is part of JLPT N1 vocabulary.
Example sentence
新幹線なら、名古屋から東京もそんなに遠く感じないよ。
If you travel by Shinkansen, it doesn't seem far from Nagoya to Tokyo.