Historical clue formulations

• Ten: Prefix — 2023-06-21
• Prefix with -hedron — 2020-07-18
• Ten: Prefix — 2018-03-12
• Numerical prefix — 2018-01-12
• Easily passed — 2013-08-29
• Ten, for openers — 2013-01-20
• Numerical prefix — 2011-01-23
• Prefix meaning 27-Down — 2010-06-16
• Prefix with -gon — 2010-01-24
• Prefix with -gon — 2006-04-02
• Numerical prefix — 2006-03-01
• Numerical prefix — 2004-11-07
• Prefix with pod — 2002-08-22
• Ten: Prefix — 2002-06-04
• Ten: Prefix — 2002-01-28
• Numerical prefix — 2002-01-10
• Prefix with -gon — 2001-11-11
• Geometric prefix — 1999-05-01
• Ten, for openers — 1998-12-16
• Ten: Prefix — 1998-05-11
• Ten in front? — 1998-03-27
• Prefix with -gon — 1996-11-03
• Numerical prefix — 1996-03-02
• Ten: Prefix — 1995-05-15
• Prefix with -hedron — 1995-04-11