antagonistic

adj

1.
indicating opposition or resistance
counter
Derived from:
antagonism antagonist
2.
characterized by antagonism or antipathy
antipathetic antipathetical
Derived from:
antagonism
3.
arousing animosity or hostility
fightsome foe
Antonym:
conciliatory
Derived from:
antagonism
4.
used especially of drugs or muscles that counteract or neutralize each other's effect
witherward incompatible
Antonym:
synergistic
Derived from:
antagonism antagonist
5.
incapable of harmonious association
Derived from:
antagonism