#1 relapse n. [backsliding, lapse, lapsing, relapsing, reversion, reverting] a failure to maintain a higher state. wn
#2 relapse v. [get worse] deteriorate in health; "he relapsed". wn
#3 relapse v. [lapse, recidivate, regress, retrogress, fall back] go back to bad behavior; "Those who recidivate are often minor criminals". wn
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