level vs vary

level

verb
  • To adjust or adapt to a certain level. 

  • To direct or impose (a penalty, fine, etc) at or upon (someone). 

  • To make the score of a game equal. 

  • To bring to a common level or plane, in respect of rank, condition, character, privilege, etc. 

  • To speak honestly and openly with. 

  • To adjust so as to make as flat or perpendicular to the ground as possible. 

  • To progress to the next level. 

  • To aim or direct (a weapon, a stare, an accusation, etc). 

  • To destroy by reducing to ground level; to raze. 

noun
  • A floor of a multi-storey building. 

  • A school grade or year. 

  • Distance from the root node of a tree structure. 

  • Degree or amount. 

  • A numeric value that quantifies a character, ability, or item's experience and power. 

  • An area of almost perfectly flat land. 

  • One of the specific values which may be taken by a categorical variable. 

  • Achievement or qualification. 

  • A distance relative to a given reference elevation. 

  • A tool for finding whether a surface is level, or for creating a horizontal or vertical line of reference. 

  • One of several discrete segments of a game, generally increasing in difficulty and representing different locations in the game world. 

adj
  • In the same position or rank. 

  • Perpendicular to a gravitational force. 

  • Unvaried in volume. 

  • Of even tone; without rising or falling inflection; monotonic. 

  • Unvaried in frequency. 

  • Well balanced; even; just; steady; impartial. 

  • The same height at all places; parallel to a flat ground. 

  • Calm. 

  • At the same height as some reference; constructed as level with. 

  • Straightforward; direct; clear. 

vary

verb
  • To institute a change in, from a current state; to modify. 

  • To make of different kinds; to make different from one another; to diversity; to variegate. 

  • To embellish; to change fancifully; to present under new aspects, as of form, key, measure, etc. See variation. 

  • To be or act different from the usual. 

  • Not to remain constant: to change with time or a similar parameter. 

  • To change with time or a similar parameter. 

  • To display differences. 

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