1. The relation between opposing principles, forces or factors
   "the inherent antagonism of capitalism and socialism"
    
2. A state of deep-seated ill-will
   "The antagonism between the two nations had historical roots";
   - hostility, enmity
    
3. An actively expressed feeling of dislike and hostility
   "The antagonism between the two political parties was evident in their debates"
    
4. (biochemistry) interference in or inhibition of the physiological action of a chemical substance by another having a similar structure
   "The drug's effectiveness was reduced due to antagonism from a similar compound"

Derived forms: antagonisms

Type of: dislike, enmity, hinderance [rare], hindrance, hostility, ill will, interference, oppositeness, opposition, state

Encyclopedia: Antagonism