Pronounced /piænoʊ/ for meaning 1, and /piɑ:noʊ/ for meaning 2.
1.
A piano is a large musical instrument with a row of black and white keys. When you press these keys with your fingers, little hammers hit wire strings inside the piano which vibrate to produce musical notes.
I taught myself how to play the piano...
He started piano lessons at the age of 7.
...sonatas for cello and piano.
N-VAR : oft the N
see also grand piano , upright piano
2.
A piece of music that is played piano is played quietly. ( TECHNICAL )
ADV : ADV after v