On-again is a phrase that means resuming or restarting a relationship or an activity that has been interrupted. Some synonyms for on-again might include the words renewed, resumed, or recommenced. Other similar phrases that convey the same meaning include back on track, back in action, or back in the saddle. These phrases all convey the idea of picking up where you left off after a pause or a break. Whether it's a relationship, a project, or a hobby, finding the right words to describe the action of picking it back up can help you convey your intent and enthusiasm.