Underperforming rhymes with:
outperforming, outperforming, outperforming, barnstorming, brainstorming, heartwarming, outperforming, alarming, arming, barnstorming, brainstorming, charming, conforming, disarming, farming, forming, harming, heartwarming, informing, misinforming, nonperforming, norming, outperforming, performing, rearming, reforming, storming, swarming, transforming, warming