ＩＮ

What does ＩＮ mean in English?

1. in (of a ball, in tennis, etc.); inside the line(n)
2. in; inside; internal; interior(adj-f)
3. enter here; enter; entrance; (parking) entry(unc)
4. back nine (golf)(n)
5. inside lane (track cycling, speed skating, etc.)(n)