antithesis

/an-ˈti-thə-səs/

Late Latin, from Greek, literally, opposition, from antitithenai to oppose, from anti- + tithenai to set

noun

  1. the direct opposite

  2. the rhetorical contrast of ideas by means of parallel arrangements of words, clauses, or sentences (as in "action, not words" or "they promised freedom and provided slavery")

  3. opposition, contrast

Her temperament is the very antithesis of mine.