Define the Great Line is the fifth studio album by American rock band Underoath. It was released on June 20, 2006.
| No. | Title | Length |
|---|---|---|
| 1. | "In Regards to Myself" | 3:24 |
| 2. | "A Moment Suspended in Time" | 3:59 |
| 3. | "There Could Be Nothing After This" | 3:26 |
| 4. | "You're Ever So Inviting" | 4:13 |
| 5. | "Sálmarnir" | 2:57 |
| 6. | "Returning Empty Handed" | 4:27 |
| 7. | "Casting Such a Thin Shadow" | 6:13 |
| 8. | "Moving for the Sake of Motion" | 3:15 |
| 9. | "Writing on the Walls" | 4:02 |
| 10. | "Everyone Looks So Good from Here" | 2:56 |
| 11. | "To Whom It May Concern" | 7:02 |
| Total length: | 45:54 | |