Entrance
Admission, Entering
The location from which you enter is where you make your entrance. It has to do with things like "entrance fees" and "entrance was not permitted," etc.
にゅうじょう
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
会場に入場するには、チケットが必ようです。
You need a ticket to enter the venue.
さいしゅう入場時かんは午後五時です。
Last admission is at 5 pm.
ちくしょう！「確実な死への部屋」への入場門が塞がれている。
Damn it! The entrance to the "Room of Certain Death" is blocked.