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
2. Peaceful; favorable to, or characterized by, the music of
the pipe rather than of the drum and fife. --Shak.
3. Emitting a high, shrill sound.
4. Simmering; boiling; sizzling; hissing; -- from the sound
of boiling fluids.
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
Piping hot, boiling hot; hissing hot; very hot. [Colloq.]