Trisection is the division of a quantity, figure, etc. into three equal parts, i.e., 
-multisection
with 
.
Trisection
See also
Angle Trisection, Bisection, Multisection, Trisected Perimeter Point, TrisectrixExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Trisection." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Trisection.html