Facet Modeling > Facet Handling > Refine > About Refining the Faceted Geometry
  
About Refining the Faceted Geometry
The Facet > Refine command improves the surface of the facet model by making the mesh denser by subdividing the existing facets. This results in an increased number of facets in the selected area. Using this command results in a more detailed and smoother selected region.