Historical clue formulations

• Figure with equal angles — 2022-10-16
• Geometric figure with equal angles — 2020-06-24
• Equiangular shape — 2017-11-08
• Rectangle or square — 2007-04-28
• Geometric figure with all equal angles — 2003-09-06
• Equiangular geometrical shape — 1996-12-25