The Collaborative International Dictionary of English v.0.48:

Pipe \Pipe\, v. t. [imp. & p. p. Piped; p. pr. & vb. n.
   Piping.]
   1. To perform, as a tune, by playing on a pipe, flute, fife,
      etc.; to utter in the shrill tone of a pipe.
      [1913 Webster]

            A robin . . . was piping a few querulous notes. --W.
                                                  Irving.
      [1913 Webster]

   2. (Naut.) To call or direct, as a crew, by the boatswain's
      whistle.
      [1913 Webster]

            As fine a ship's company as was ever piped aloft.
                                                  --Marryat.
      [1913 Webster]

   3. To furnish or equip with pipes; as, to pipe an engine, or
      a building.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Piping \Pip"ing\ (p[imac]p"[i^]ng), a. [From Pipe, v.]
   1. Playing on a musical pipe. "Lowing herds and piping
      swains." --Swift.
      [1913 Webster]

   2. Peaceful; favorable to, or characterized by, the music of
      the pipe rather than of the drum and fife. --Shak.
      [1913 Webster]

   3. Emitting a high, shrill sound.
      [1913 Webster]

   4. Simmering; boiling; sizzling; hissing; -- from the sound
      of boiling fluids.
      [1913 Webster]

   Piping crow, Piping crow shrike, Piping roller (Zool.),
      any Australian bird of the genus Gymnorhina, esp.
      Gymnorhina tibicen, which is black and white, and the
      size of a small crow. Called also caruck.

   Piping frog (Zool.), a small American tree frog (Hyla
      Pickeringii) which utters a high, shrill note in early
      spring.

   Piping hot, boiling hot; hissing hot; very hot. [Colloq.]
      --Milton.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Piping \Pip"ing\, n.
   1. A small cord covered with cloth, -- used as trimming for
      women's dresses.
      [1913 Webster]

   2. Pipes, collectively; as, the piping of a house.
      [1913 Webster]

   3. The act of playing on a pipe; the shrill noted of birds,
      etc.
      [1913 Webster]

   4. A piece cut off to be set or planted; a cutting; also,
      propagation by cuttings.
      [1913 Webster] Pipistrel

The Collaborative International Dictionary of English v.0.48:

high-pitched \high-pitched\ adj.
   1. high in pitch or frequency; -- used of sounds and voices.
      Opposite of low. [Narrower terms: adenoidal, pinched,
      nasal; altissimo; alto; countertenor, alto;
      falsetto; peaky, spiky; piping; shrill, sharp;
      screaky, screechy, squeaking, squeaky, squealing;
      soprano, treble; sopranino; tenor]

   Syn: high.
        [WordNet 1.5]

   2. set at a sharp or high angle or slant; as, a high-pitched
      roof.

   Syn: steeply pitched, steep.
        [WordNet 1.5] high-power

WordNet (r) 3.0 (2006):

piping
    adv 1: (used of heat) extremely; "the casserole was piping hot"
           [syn: piping, steaming]
    n 1: a thin strip of covered cord used to edge hems
    2: a long tube made of metal or plastic that is used to carry
       water or oil or gas etc. [syn: pipe, pipage, piping]
    3: playing a pipe or the bagpipes

Moby Thesaurus II by Grady Ward, 1.0:

100 Moby Thesaurus words for "piping":
   acute, adjutage, argute, at peace, balmy, bloodless, blooming,
   blossoming, booming, calm, catheter, clear, concordant, creaky,
   drainpipe, ear-piercing, efflux tube, exuberant, fair, fat,
   fire hose, flourishing, flowering, flue pipe, fruiting, funnel,
   garden hose, gas pipe, going strong, halcyon, high, hose, hosepipe,
   howling, idyllic, in full swing, in good case, keen, keening,
   nipple, orderly, organ pipe, pacific, palmy, pastoral, peaceable,
   peaceful, peacetime, penetrating, piercing, pipe, pipeline,
   pipette, prospering, quiet, reed, reed pipe, reedy, restful, rosy,
   screaky, screeching, screechy, serene, sharp, shrieking, shrieky,
   shrill, siamese, siamese connection, siphon, sleek, snorkel, soft,
   soil pipe, squeaking, squeaky, standpipe, steam pipe, stem, straw,
   tap, thin, thriving, tranquil, treble, tube, tubing, tubulation,
   tubule, tubulet, tubulure, ululant, untroubled, vigorous, wailing,
   waste pipe, water pipe, whining, whistling



The Free On-line Dictionary of Computing (30 December 2018):

pipe
piping

   1.  One of Unix's buffers which can be
   written to by one asynchronous process and read by another,
   with the kernel suspending and waking up the sender and
   receiver according to how full the pipe is.  In later versions
   of Unix, rather than using an anonymous kernel-managed
   temporary file to implement a pipe, it can be named and is
   implemented as a local socket pair.

   2.  "|" ASCII character 124.  Used to represent a
   pipe between two processes in a shell command line.  E.g.

   	grep foo log | more

   which feeds the output of grep into the input of more without
   requiring a named temporary file and without waiting for the
   first process to finish.

   3.  A connection to a network.

   See also light pipe.

   (1996-09-24)