antithetical
1. [ adjective ] sharply contrasted in character or purpose
Synonyms: antithetic
Examples:

"practices entirely antithetical to her professed beliefs" "hope is antithetic to despair"

Related terms: different
Similar spelling:   antithetically
  antithetic
  antitypical
  antitypic
  antitoxic
  antidiuretic
  antidiabetic
  antithesis
  antithyroid