fluctuation vs variety

fluctuation

noun
  • A motion like that of waves; a moving in this and that direction. 

  • A wavering; unsteadiness. 

  • In medicine, a wave-like motion or undulation of a fluid in a natural or abnormal cavity (e.g. pus in an abscess), which is felt during palpation or percussion. 

variety

noun
  • A specific variation of something. 

  • A rank in a taxonomic classification below species and (if present) subspecies, and above form; hence, an organism of that rank. 

  • The total number of distinct states of a system; also, the logarithm to the base 2 of the total number of distinct states of a system. 

  • An animal or plant (or a group of such animals or plants) with characteristics causing it to differ from other animals or plants of the same species; a cultivar. 

  • In universal algebra: an equational class; the class of all algebraic structures of a given signature, satisfying a given set of identities. 

  • A specific form of a language, neutral to whether that form is an accent, dialect, register, etc., and to its prestige level; an isolect or lect. 

  • A collection or number of different things. 

  • The kind of entertainment given in variety performances or shows; also, the production of, or performance in, variety performances or shows. 

  • A deviation or difference. 

  • A stamp, or set of stamps, which has one or more characteristics (such as colour, paper, etc.) differing from other stamps in the same issue, especially if such differences are intentionally introduced. 

  • The quality of being varied; diversity. 

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