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

piano \pian"o\, pianoforte \pian"ofor`te\, n. it. piano soft
   fr. l. planus even, smooth; see plain, a. + it. forte
   strong, fr. l. fortis see fort. mus.
   a well-known musical instrument somewhat resembling the
   harpsichord, and consisting of a series of wires of graduated
   length, thickness, and tension, struck by hammers moved by
   keys.
   1913 webster

   dumb piano. see digitorium.

   grand piano. see under grand.

   square piano, one with a horizontal frame and an oblong
      case.

   upright piano, one with an upright frame and vertical
      wires.
      1913 webster
see also:
plain fort dumb piano digitorium grand piano grand 
square piano upright piano 

[2] : WordNet (r) 2.0

upright piano
     n : a piano with a vertical sounding board syn: upright
see also:
upright 

Upright Piano >> U Words
Upright Piano, definition of term: Upright Piano
upright+piano_pag1.html

Upright >> U Words
Upright, definition of term: Upright
upright_pag1.html

Piano >> P Words
Piano, definition of term: Piano
piano_pag1.html

Grand Piano >> G Words
Grand Piano, definition of term: Grand Piano
grand+piano_pag1.html