notch in a train ticket; punch mark
Rare term for the small notch or hole left by a ticket punch, especially on old-style train tickets. Mostly encountered in historical or railway-enthusiast contexts.
Old tickets had a punch mark put in them at the ticket gate.
Mixed kanji-kana spelling; こん replaces the rare kanji 痕.
A Sino-Japanese compound of 鋏 “scissors or ticket punch” and 痕 “mark, trace,” denoting the mark made by punching a ticket.