As nouns the difference between xylophone and piano
is that xylophone
is a musical instrument made of wooden slats graduated so as to make the sounds of the scale when struck with a small drumstick-like hammer while piano
is a keyboard musical instrument, usually ranging over seven octaves, with white and black keys, played by pressing these keys, causing hammers to strike strings.
As an adjective piano is
As an adverb piano is
softly, as a musical direction (abbreviated to p.
in sheet music).