| 2025-09-17 | Outie's counterpart |
| 2025-05-04 | Concave umbilicus |
| 2025-03-27 | Result of some cord-cutting, informally |
| 2025-02-19 | Navel type |
| 2024-01-17 | Bellybutton type, informally |
| 2023-01-12 | Feature of many a belly |
| 2022-01-23 | It might gather lint |
| 2021-09-01 | Body feature for roughly 90% of people |
| 2021-03-28 | Navel type |
| 2019-10-27 | What many a navel-gazer gazes at |
| 2019-08-21 | Certain navel |
| 2018-08-26 | Navel formation? |
| 2018-05-05 | Roughly nine of 10 people have one |
| 2017-03-05 | Certain navel |
| 2016-02-23 | Belly button type |
| 2015-11-02 | Belly button type |
| 2014-04-30 | Belly button type |
| 2013-11-25 | Concave belly button |
| 2013-10-01 | Certain belly button |
| 2013-05-26 | Concave object of reflection? |
| 2010-10-24 | Hole just above a belt |
| 2010-02-05 | About 90% of people have one |
| 2009-12-08 | Certain navel |
| 2008-12-30 | Certain navel |
| 2008-12-05 | Omphalos variety |
| 2008-10-10 | It doesn't come out of the stomach |
| 2008-05-19 | Concave belly button |
| 2008-05-08 | Concave lint trap? |
| 2008-04-01 | Type of 39-Down |
| 2008-03-09 | Concave button |
| 2007-02-25 | Navel type |
| 2007-02-07 | Belly button type |
| 2006-07-25 | Lint-collecting bellybutton |
| 2006-06-16 | Feature of many a stomach |
| 2006-02-22 | Certain belly button |
| 2005-11-14 | Navel type |
| 2005-06-12 | Navel type |
| 2004-12-14 | Many a navel |
| 2004-07-18 | Certain navel |
| 2003-04-22 | Bellybutton type |
| 2001-06-03 | Nonprotruding navel |
| 1999-03-31 | Bellybutton type |
| 1998-02-26 | Navel type |