In a conchoidal manner.

(mathematics) Of or pertaining to a conchoid; that may be defined as a conchoid. / (mineralogy, of a fracture) Irregular, with planar, concentric curves, similar to those on a mussel shell.

(mathematics, geometry) Any of a family of curves defined as the locus of points p, such that each p is on a line that passes through a given fixed point P and intersects a given curve, C, and the distance from p to the point of intersection with C is a specified constant (note that for nontrivial cases two such points p satisfy the criteria, and the resultant curve has two parts).

plural of conchoid