to laugh in the sleeve

Sleeve \Sleeve\, n. [OE. sleeve, sleve, AS. sl?fe, sl?fe; akin
   to sl?fan to put on, to clothe; cf. OD. sloove the turning up
   of anything, sloven to turn up one's sleeves, sleve a sleeve,
   G. schlaube a husk, pod.]
   1. The part of a garment which covers the arm; as, the sleeve
      of a coat or a gown. --Chaucer.
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   2. A narrow channel of water. [R.]
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            The Celtic Sea, called oftentimes the Sleeve.
                                                  --Drayton.
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   3. (Mach.)
      (a) A tubular part made to cover, sustain, or steady
          another part, or to form a connection between two
          parts.
      (b) A long bushing or thimble, as in the nave of a wheel.
      (c) A short piece of pipe used for covering a joint, or
          forming a joint between the ends of two other pipes.
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   4. (Elec.) A double tube of copper, in section like the
      figure 8, into which the ends of bare wires are pushed so
      that when the tube is twisted an electrical connection is
      made. The joint thus made is called

   {a McIntire joint}.
      [Webster 1913 Suppl.]

   {Sleeve button}, a detachable button to fasten the wristband
      or cuff.

   {Sleeve links}, two bars or buttons linked together, and used
      to fasten a cuff or wristband.

   {To laugh in the sleeve} or {To laugh up one's sleeve} to
      laugh privately or unperceived, especially while
      apparently preserving a grave or serious demeanor toward
      the person or persons laughed at; that is, perhaps,
      originally, by hiding the face in the wide sleeves of
      former times.

   {To pinon the sleeve of}, or {To hang on the sleeve of}, to
      be, or make, dependent upon.
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Laugh \Laugh\ (l[aum]f), v. i. [imp. & p. p. {Laughed}
   (l[aum]ft); p. pr. & vb. n. {Laughing}.] [OE. laughen,
   laghen, lauhen, AS. hlehhan, hlihhan, hlyhhan, hliehhan; akin
   to OS. hlahan, D. & G. lachen, OHG. hlahhan, lahhan,
   lahh[=e]n, Icel. hl[ae]ja,W Dan. lee, Sw. le, Goth. hlahjan;
   perh. of imitative origin.]
   1. To show mirth, satisfaction, or derision, by peculiar
      movement of the muscles of the face, particularly of the
      mouth, causing a lighting up of the face and eyes, and
      usually accompanied by the emission of explosive or
      chuckling sounds from the chest and throat; to indulge in
      laughter.
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            Queen Hecuba laughed that her eyes ran o'er. --Shak.
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            He laugheth that winneth.             --Heywood's
                                                  Prov.
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   2. Fig.: To be or appear gay, cheerful, pleasant, mirthful,
      lively, or brilliant; to sparkle; to sport.
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            Then laughs the childish year, with flowerets
            crowned.                              --Dryden.
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            In Folly's cup still laughs the bubble Joy. --Pope.
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   {To laugh at}, to make an object of laughter or ridicule; to
      make fun of; to deride.
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            No wit to flatter left of all his store,
            No fool to laugh at, which he valued more. --Pope.
      

   {To laugh in the sleeve}, {To laugh up one's sleeve}, to
      laugh secretly, or so as not to be observed, especially
      while apparently preserving a grave or serious demeanor
      toward the person or persons laughed at.

   {To laugh out}, to laugh in spite of some restraining
      influence; to laugh aloud.

   {To laugh out of the other corner of the mouth} or {To laugh
   out of the other side of the mouth}, to weep or cry; to feel
      regret, vexation, or disappointment after hilarity or
      exaltation. [Slang]
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