Source : Webster's Revised Unabridged Dictionary (1913)

Lapse \Lapse\, v. i. [imp. & p. p. {Lapsed}; p. pr. & vb. n.
   {Lapsing}.]
   1. To pass slowly and smoothly downward, backward, or away;
      to slip downward, backward, or away; to glide; -- mostly
      restricted to figurative uses.

            A tendency to lapse into the barbarity of those
            northern nations from whom we are descended.
                                                  --Swift.

            Homer, in his characters of Vulcan and Thersites,
            has lapsed into the burlesque character. --Addison.

   2. To slide or slip in moral conduct; to fail in duty; to
      fall from virtue; to deviate from rectitude; to commit a
      fault by inadvertence or mistake.

            To lapse in fullness Is sorer than to lie for need.
                                                  --Shak.

   3. (Law)
      (a) To fall or pass from one proprietor to another, or
          from the original destination, by the omission,
          negligence, or failure of some one, as a patron, a
          legatee, etc.
      (b) To become ineffectual or void; to fall.

                If the archbishop shall not fill it up within
                six months ensuing, it lapses to the king.
                                                  --Ayliffe.

Lapsed \Lapsed\, a.
   1. Having slipped downward, backward, or away; having lost
      position, privilege, etc., by neglect; -- restricted to
      figurative uses.

            Once more I will renew His lapsed powers, though
            forfeit.                              --Milton.

   2. Ineffectual, void, or forfeited; as, a lapsed policy of
      insurance; a lapsed legacy.

   {Lapsed devise}, {Lapsed legacy} (Law), a devise, or legacy,
      which fails to take effect in consequence of the death of
      the devisee, or legatee, before that of the testator, or
      for ether cause. --Wharton (Law Dict.).

Source : WordNet®

lapsed
     adj : no longer active or practicing; "a lapsed Catholic" [syn: {nonchurchgoing}]