zorkru lujvo

x1 is a concave curve/turn/bend in x2, at locus x3, and defined by set of points/properties x4.

Also: x1 is concave. Convex: ze'okru. See also: zo'i, kruvi.

In notes:

ze'okru
x1 is a convex curve/turn/bend in x2, at locus x3, and defined by set of points/properties x4.