The Collaborative International Dictionary of English v.0.48:

French \French\ (fr[e^]nch), prop. a. [AS. frencisc, LL.
   franciscus, from L. Francus a Frank: cf. OF. franceis,
   franchois, fran[,c]ois, F. fran[,c]ais. See Frank, a., and
   cf. Frankish.]
   Of or pertaining to France or its inhabitants.
   [1913 Webster]

   French bean (Bot.), the common kidney bean (Phaseolus
      vulgaris).

   French berry (Bot.), the berry of a species of buckthorn
      (Rhamnus catharticus), which affords a saffron, green or
      purple pigment.

   French casement (Arch.) See French window, under
      Window.

   French chalk (Min.), a variety of granular talc; -- used
      for drawing lines on cloth, etc. See under Chalk.

   French cowslip (Bot.) The Primula Auricula. See
      Bear's-ear.

   French fake (Naut.), a mode of coiling a rope by running it
      backward and forward in parallel bends, so that it may run
      freely.

   French honeysuckle (Bot.) a plant of the genus Hedysarum
      (H. coronarium); -- called also garland honeysuckle.


   French horn, a metallic wind instrument, consisting of a
      long tube twisted into circular folds and gradually
      expanding from the mouthpiece to the end at which the
      sound issues; -- called in France cor de chasse.

   French leave, an informal, hasty, or secret departure;
      esp., the leaving a place without paying one's debts.

   French pie [French (here used in sense of "foreign") + pie
      a magpie (in allusion to its black and white color)]
      (Zool.), the European great spotted woodpecker (Dryobstes
      major); -- called also wood pie.

   French polish.
   (a) A preparation for the surface of woodwork, consisting of
       gums dissolved in alcohol, either shellac alone, or
       shellac with other gums added.
   (b) The glossy surface produced by the application of the
       above.

   French purple, a dyestuff obtained from lichens and used
      for coloring woolen and silken fabrics, without the aid of
      mordants. --Ure.

   French red rouge.

   French rice, amelcorn.

   French roof (Arch.), a modified form of mansard roof having
      a nearly flat deck for the upper slope.

   French tub, a dyer's mixture of protochloride of tin and
      logwood; -- called also plum tub. --Ure.

   French window. See under Window.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Leave \Leave\, n. [OE. leve, leave, AS. le['a]f; akin to le['o]f
   pleasing, dear, E. lief, D. oorlof leave, G. arlaub, and
   erlauben to permit, Icel. leyfi. [root]124. See Lief.]
   1. Liberty granted by which restraint or illegality is
      removed; permission; allowance; license.
      [1913 Webster]

            David earnestly asked leave of me.    --1 Sam. xx.
                                                  6.
      [1913 Webster]

            No friend has leave to bear away the dead. --Dryden.
      [1913 Webster]

   2. The act of leaving or departing; a formal parting; a
      leaving; farewell; adieu; -- used chiefly in the phrase,
      to take leave, i. e., literally, to take permission to go.
      [1913 Webster]

            A double blessing is a'double grace;
            Occasion smiles upon a second leave.  --Shak.
      [1913 Webster]

            And Paul after this tarried there yet a good while,
            and then took his leave of the brethren. --Acts
                                                  xviii. 18.
      [1913 Webster]

   French leave. See under French.

   Syn: See Liberty.
        [1913 Webster]

WordNet (r) 3.0 (2006):

French leave
    n 1: an abrupt and unannounced departure (without saying
         farewell)

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "French leave":
   AWOL, abscondence, absence, absence without leave, absentation,
   absenteeism, absenting, absquatulation, bolt, cut, day off,
   decampment, default, departure, desertion, disappearance,
   disappearing act, elopement, escape, excused absence, exit,
   fleeing, flight, fugitation, furlough, hasty retreat, hegira,
   holiday, hooky, leave, leave of absence, leaving, nonappearance,
   nonattendance, quick exit, running away, sabbatical leave,
   scramming, sick leave, skedaddle, skedaddling, truancy, truantism,
   unexcused absence, vacation