| 2026-01-20 | Prefix for element #8 |
| 2024-12-03 | Lead-in to -tocin |
| 2022-08-10 | Big name in acne medication |
| 2022-06-25 | Competitor of Stridex |
| 2021-11-22 | Popular acne medication |
| 2018-09-23 | Houston-based petroleum giant, informally |
| 2018-01-04 | Acne medication brand |
| 2015-11-29 | Sister brand of Phisoderm |
| 2015-08-23 | California school attended by Obama, familiarly |
| 2013-12-16 | Clearasil rival |
| 2012-04-26 | ___ 10 (acne-fighting medicine) |
| 2011-12-10 | Moronic beginning? |
| 2010-06-20 | ___-10 (acne medication) |
| 2008-07-27 | International oil and gas giant, informally |
| 2007-01-10 | Acne treatment brand |
| 2005-07-27 | Prefix with acetylene |
| 2005-04-25 | Prefix with acetylene |
| 2002-12-16 | Prefix with acetylene |
| 2002-04-19 | Prefix with tetracycline |
| 2001-01-07 | Big oil company, for short |
| 2000-11-07 | Prefix with acetylene |
| 2000-05-01 | Nickname in the oil biz |
| 2000-03-29 | ___-10 (acne-fighting medicine) |
| 2000-01-28 | Big oil company, informally |
| 1994-11-28 | Petroleum company, informally |
| 1994-06-10 | Acetylene starter |