1. (v. i.) To slip or slide back, to suffer a return of a disease\.

2. (v. i.) To slide or turn back into a former state or practice; to fall back from some condition attained; -- generally in a bad sense, as from a state of convalescence or amended condition; as, to relapse into a stupor, into vice, or into barbarism; -- sometimes in a good sense; as, to relapse into slumber after being disturbed.

3. (v. i.) To fall from Christian faith into paganism, heresy, or unbelief; to backslide.

4. (n.) A sliding or falling back, especially into a former bad state, either of body or morals; backsliding; the state of having fallen back.

5. (n.) One who has relapsed, or fallen back, into error; a backslider; specifically, one who, after recanting error, returns to it again.

about-face apostasy backing backset backslide backsliding backward motion backward step cock decline degenerate degeneration deteriorate deterioration disenchantment disimprove fade fading fail failing failure fall fall again into fall astern fall back fall behind fall from grace falling back flip-flop get back get behind get worse go back go backwards go behind grow worse have a relapse jerk back lapse lapse back lapsing let down lose ground pull back reaction recede recession recidivate recidivation recidivism reclamation reconversion recur to reentry refluence reflux regress regressing regression rehabilitation reinstatement restitution restoration retreat retroaction retrocede retrocession retroflex retroflexion retrogradation retrograde retrogress retrogression retroversion retrovert retrusion return return to returning reversal reverse reversion revert revert to reverting revulsion rollback setback sicken sink sink back sinking slacken slide back slip back slipping back sternway throwback turn turnabout weaken weakening worsen worsening yield again to