What is "reuleaux"

Reuleaux may refer to:

• Franz Reuleaux, a German mechanical engineer and lecturer, 1829 – 1905
• in geometry:
  • Reuleaux polygon, a curve of constant width
    • Reuleaux triangle, a Reuleaux polygon with three sides
    • Reuleaux heptagon, a Reuleaux polygon with seven sides that provides the shape of some currency coins
  • Reuleaux tetrahedron, the intersection of four spheres of equal radius centered at the vertices of a regular tetrahedron