| used especially of drugs or muscles that work together so the total effect is greater than the sum of the two (or more) | arousing animosity or hostility |
| of or relating to the theological doctrine of synergism | used especially of drugs or muscles that counteract or neutralize each other's effect |
| working together; used especially of groups, as subsidiaries of a corporation, cooperating for an enhanced effect | characterized by antagonism or antipathy |
| | incapable of harmonious association |
| | indicating opposition or resistance |