The phrase "bargaining on" refers to trying to negotiate or come to an agreement on something. Its antonyms are rejecting, refusing, and disagreeing. Rejecting means to decline an offer or proposal. Refusing means to say no or decline to do something that has been suggested. Disagreeing means to have a different opinion or not be able to come to an agreement. When someone is bargaining on something, they are hoping to find a middle ground or compromise. However, if they reject, refuse, or disagree, they are not willing to make concessions or compromise on the matter.