an vs over

an

prep
  • In each; to or for each; per. 

noun
  • The first letter of the Georgian alphabet, ა (Mkhedruli), Ⴀ (Asomtavruli) or ⴀ (Nuskhuri). 

article
  • Used before one and words with initial u, eu. 

  • Used before a vowel sound. 

  • Used before all consonants. 

  • Used before /h/ in an unstressed syllable. 

  • Used before /h/ in a stressed syllable. 

num
  • one 

over

prep
  • Concerning or regarding. 

  • More than; to a greater degree. 

  • Across or spanning. 

  • From one physical position to another via an obstacle that must be traversed vertically, first upwards and then downwards. 

  • Indicating relative status, authority, or power 

  • Above, implying superiority after a contest; in spite of; notwithstanding. 

  • Finished with; done with; from one state to another via a hindrance that must be solved or defeated; or via a third state that represents a significant difference from the first two. 

  • In such a way as to cover. 

  • As compared to. 

  • Divided by. 

  • On top of; above; higher than; further up. 

  • Beyond; past; exceeding; too much or too far. 

  • Separates the three of a kind from the pair in a full house. 

  • While using, especially while consuming. 

adj
  • Discontinued; ended or concluded. 

adv
  • To an excessive degree; overly. 

  • From one side of something to another, passing above it. 

  • Thoroughly; completely; from beginning to end. 

  • From an upright position to a horizontal one. 

  • From one position or state to another. 

  • Overnight (throughout the night). 

  • Again; another time; once more; over again. 

  • Horizontally; left to right or right to left. 

noun
  • A set of six legal balls bowled. 

  • Any surplus amount of money, goods delivered, etc. 

intj
  • A radio procedure word meaning that the station is finished with its transmission and is expecting a response. 

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