Source : Webster's Revised Unabridged Dictionary (1913)

Relapse \Re*lapse"\ (r?-l?ps"), v. i. [imp. & p. p. {Relapsed}
   (-l?pst"); p. pr. & vb. n. {Relapsing}.] [L. relapsus, p. p.
   of relabi to slip back, to relapse; pref. re- re- + labi to
   fall, slip, slide. See {Lapse}.]
   1. To slip or slide back, in a literal sense; to turn back.
      [Obs.] --Dryden.

   2. 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.

            That task performed, [preachers] relapse into
            themselves.                           --Cowper.

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

            They enter into the justified state, and so continue
            all along, unless they relapse.       --Waterland.

Relapsing \Re*laps"ing\, a.
   Marked by a relapse; falling back; tending to return to a
   former worse state.

   {Relapsing fever} (Med.), an acute, epidemic, contagious
      fever, which prevails also endemically in Ireland, Russia,
      and some other regions. It is marked by one or two
      remissions of the fever, by articular and muscular pains,
      and by the presence, during the paroxism of spiral
      bacterium ({Spiroch[ae]te}) in the blood. It is not
      usually fatal. Called also {famine fever}, and {recurring
      fever}.

Source : WordNet®

relapsing
     n : a failure to maintain a higher state [syn: {backsliding}, {lapse},
          {lapsing}, {relapse}, {reversion}, {reverting}]