入場（にゅうじょう） means entry/admission into a controlled venue, such as a stadium, theater, museum, or theme park.
It is more formal and specific than 入る（はいる）, which simply means “to enter.” 入場 often suggests a process: going through a gate, showing a ticket, or being allowed into an event space.
Common related words:
- 入場券（にゅうじょうけん）: admission ticket
- 入場料（にゅうじょうりょう）: entrance fee
- 入場する（にゅうじょうする）: to enter/admit oneself into a venue
The opposite is 退場（たいじょう）, meaning leaving a venue or being removed/sent off, especially in sports or events.