Translation guide
The musical instrument. In Japanese, it is almost always ピアノ (piano). The older term 洋琴 (ようきん) is rare and literary.
Referring to the keyboard instrument
The standard word for piano in Japanese. Used in all contexts.
私はピアノを弾きます。
I play the piano.
このピアノはとても古いです。
This piano is very old.
An older, literary term for piano. Rarely used in modern Japanese.
He was a master of the piano.