adj.
1.indicating opposition or resistance
2.characterized by antagonism or antipathy
3.arousing animosity or hostility
4.used especially of drugs or muscles that counteract or neutralize each other's effect
5.opposing or neutralizing or mitigating an effect by contrary action
6.incapable of harmonious association
Idiom of the Day
bet on the wrong horse
to misjudge a coming event, to misread the future
I think that my uncle bet on the wrong horse by investing all of his money in the new stock.