1. entrance

2. entry, entering, admission, entryway

3. entry (linear algebra)

4. driveway

5. ticket

6. entrance fee

7. gateway, gate

8. starter, appetizer, entrée (food)

9. computer port (computing)

10. input (computing)

11. posting, blogpost (Internet)

12. inning (sports)

13. tackle (a play where a player attempts to take control over the ball from an opponent) (soccer, sports)

14. inlet, intake (engineering)

15. (area of) receding hairline (in the plural)

16. down payment