The harpsichord, clavichord and clavier are three such instruments.
a piano.
she plays the piano
I think she plays piano
She plays the piano and sings.
she plays the piano and does vocal.
a piano.
Lots of people.
A piano.
she plays the piano
I think she plays piano
He plays the piano and the trumbone
She plays the piano and sings.
He plays piano and guitar
she plays the piano and does vocal.
George Gershwin plays the piano!
she plays the piano
JB plays the flute and piano.