菱 - diamond (shape), water chestnut, rhombus

rhombus; rhomb; lozenge; diamond (shape)

rhombencephalon; hindbrain

water caltrop (esp. Trapa japonica); water chestnut

trapezoid bone

os trapezium; trapezium

groundhopper (esp. species Tetrix japonica)

rhombus-shaped mochi

siderite

stitching chisel; pricking iron; multi-prong punch for leather-craft

Takebishi Electric Sales Corporation

flower-shaped family crest

rhombic dodecahedron