flank vs surface

flank

noun
  • The side of something, in general senses. 

  • The flesh between the last rib and the hip; the side. 

  • The sides of a bastion perpendicular to the wall from which the bastion projects. 

  • The outermost strip of a road. 

  • The wing, one side of the pitch. 

  • That part of the acting surface of a gear wheel tooth that lies within the pitch line. 

  • A cut of meat from the flank of an animal. 

  • The extreme left or right edge of a military formation, army etc. 

verb
  • To be placed to the side(s) of something (usually in terms of two objects, one on each side). 

  • To defend the flank(s) of. 

  • To attack the flank(s) of. 

  • To place to the side(s) of. 

adj
  • Maximum. Historically faster than full speed (the most a vessel can sustain without excessive engine wear or risk of damage), now frequently used interchangeably. Typically used in an emergency or during an attack. 

surface

noun
  • Outward or external appearance. 

  • The outside hull of a tangible object. 

  • The overside or up-side of a flat object such as a table, or of a liquid. 

  • The locus of an equation (especially one with exactly two degrees of freedom) in a more-than-two-dimensional space. 

verb
  • To apply a surface to something. 

  • To make (information or facts) known. 

  • To become known or apparent; to appear or be found. 

  • To provide something with a surface. 

  • To bring to the surface. 

  • To come out of hiding. 

  • To work a mine near the surface. 

  • To rise to the surface. 

How often have the words flank and surface occurred in a corpus of books? (source: Google Ngram Viewer )