(adj)used especially of drugs or muscles that work together so the total effect is greater than the sum of the two (or more), Syn.interactive, Ant.antagonistic
n. [ Cf. F. synergiste. ] 1. One who holds the doctrine of synergism. [ 1913 Webster ]
2. (Med.) A remedy which has an action similar to that of another remedy, and hence increases the efficiency of that remedy when combined with it. [ 1913 Webster ]