Origin of equilateral
Late Latin aequilateralis, from Latin aequi- + later-, latus side — more at lateral
First Known Use: 1570
EQUILATERAL Defined for Kids
Definition of equilateral
: having all sides or faces equal <an equilateral triangle>
Seen and Heard
What made you want to look up equilateral? Please tell us where you read or heard it (including the quote, if possible).