A counter or booth where tickets (for trains, events, etc.) are sold.
駅の券売所で特急券を買った。
I bought a limited-express ticket at the station ticket counter.
コンサート当日は券売所に長い列ができた。
On the day of the concert a long line formed at the ticket booth.
券売所が閉まっていたので自動券売機で買った。
The ticket counter was closed, so I bought one from the vending machine.