piano

(noun) a keyboard instrument that is played by depressing keys that cause hammers to strike tuned strings and produce sounds. Synonyms: pianoforte, forte-piano.

(noun) (music) low loudness. Synonyms: pianissimo.

(adj) used chiefly as a direction or description in music. Synonyms: piano (vs. forte), soft. Example: "The piano passages in the composition."

(adv) used as a direction in music; to be played relatively softly. Synonyms: softly.