[1] : The Collaborative International Dictionary of English v.0.48

sleeper \sleep"er\, n.
   1. one who sleeps; a slumberer; hence, a drone, or lazy
      person.
      1913 webster

   2. that which lies dormant, as a law. obs. --bacon.
      1913 webster

   3. a sleeping car. colloq. u.s.
      1913 webster

   4. zool. an animal that hibernates, as the bear.
      1913 webster

   5. zool.
      a a large fresh-water gobioid fish eleotris
          dormatrix.
      b a nurse shark. see under nurse.
          1913 webster
see also:
eleotris dormatrix nurse 

[2] : The Collaborative International Dictionary of English v.0.48

sleeper \sleep"er\, n. cf. norw. sleip a sleeper a timber, as
   adj., slippery, smooth. see slape.
   something lying in a reclining posture or position.
   specifically: 
   1913 webster
   a one of the pieces of timber, stone, or iron, on or near
       the level of the ground, for the support of some
       superstructure, to steady framework, to keep in place the
       rails of a railway, etc.; a stringpiece.
       1913 webster
   b one of the joists, or roughly shaped timbers, laid
       directly upon the ground, to receive the flooring of the
       ground story. u.s.
       1913 webster
   c naut. one of the knees which connect the transoms to
       the after timbers on the ship's quarter.
       1913 webster
   d naut. the lowest, or bottom, tier of casks.
       1913 webster
see also:
slape 

[3] : The Collaborative International Dictionary of English v.0.48

tetard \tetard"\, n. zool.
   a gobioid fish eleotris gyrinus of the southern united
   states; -- called also sleeper.
   1913 webster
see also:
eleotris gyrinus sleeper 

[4] : WordNet (r) 2.0

sleeper
     n 1: a rester who is sleeping syn: slumberer
     2: a spy or saboteur or terrorist planted in an enemy country
        who lives there as a law-abiding citizen until activated
        by a prearranged signal
     3: an unexpected achiever of success; "the winner was a true
        sleeper--no one expected him to get it"
     4: one of the cross braces that support the rails on a railway
        track; "the british call a railroad tie a sleeper" syn: tie,
         railroad tie, crosstie
     5: a passenger car that has berths for sleeping syn: sleeping
        car, wagon-lit
     6: a piece of furniture that can be opened up into a bed
     7: tropical fish that resembles a goby and rests quietly on the
        bottom in shallow water syn: sleeper goby
     8: an unexpected hit; "that movie was the sleeper of the
        summer"
see also:
slumberer tie railroad tie crosstie sleeping car wagon-lit 
sleeper goby 

[5] : Moby Thesaurus II by Grady Ward, 1.0

128 moby thesaurus words for "sleeper":
   amytal, amytal pill, demerol, dolophine, h, luminal, luminal pill,
   m, mickey finn, nembutal, nembutal pill, pullman, pullman car,
   seconal, seconal pill, tuinal, tuinal pill, alcohol,
   amobarbital sodium, analgesic, anodyne, baggage car, barb,
   barbiturate, barbiturate pill, black stuff, blue, blue angel,
   blue devil, blue heaven, blue velvet, boxcar, caboose, calmative,
   car, carriage, chair car, chloral hydrate, coach, coal car,
   codeine, codeine cough syrup, covered waggon, day coach,
   depressant, depressor, diner, dinghy, dining car, dolly, downer,
   drawing room, flat, flatcar, gondola, goofball, hard stuff, heroin,
   hop, horse, hypnotic, junk, knockout drops, laudanum, lie-abed,
   liquor, local, lotus, luggage van, mail car, mail van, meperidine,
   methadone, morphia, morphine, narcotic, opiate, opium, pacifier,
   pain killer, palace car, paregoric, parlor car, passenger car,
   pen yan, phenobarbital, phenobarbital sodium, purple heart,
   quietener, railway car, rainbow, red, reefer, refrigerator car,
   roomette, scag, secobarbital sodium, sedative, shit, sleep-inducer,
   sleeping beauty, sleeping draught, sleeping pill, sleepwalker,
   sleepyhead, slugabed, smack, smoker, smoking car,
   sodium thiopental, somnambulist, somnifacient, somniloquist,
   soother, soothing syrup, soporific, stockcar, tank, tar, tender,
   tranquilizer, truck, turps, van, waggon, white stuff, yellow,
   yellow jacket

Sleeper >> S Words
Sleeper, definition of term: Sleeper
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