In geometry, a rhombus (pl.: rhombi or rhombuses) is an equilateral quadrilateral, a quadrilateral whose four sides all have the same length. Other names for rhombus include diamond, lozenge, and calisson.
The human feet that routinely wash ashore in the Pacific Northwest, explained (vox.com) Human feet occasionally wash up on the shores of the Salish Sea around Seattle and Vancouver. Don’t be alarmed.