relapse
     n : a failure to maintain a higher state [syn: {backsliding}, {lapse},
          {lapsing}, {relapsing}, {reversion}, {reverting}]
     v 1: deteriorate in health; "he relapsed" [syn: {get worse}]
          [ant: {get well}]
     2: go back to bad behavior; "Those who recidivate are often
        minor criminals" [syn: {lapse}, {recidivate}, {regress}, {retrogress},
         {fall back}]
Source: WordNet® 2.0