The expression fortepiano (sometimes called forte piano) is a sudden dynamic change used in a musical score, usually with the abbreviation , to designate a section of music in which the music should be played loudly (forte), then immediately softly (piano).Collins Encyclopedia of Music Page 217 It is not unusual for it to be followed by a crescendo, a gradual increase in dynamics. The word is of Italian etymology literally translated as 'loudsoft'.
Examples Beethoven's Piano Sonata No. 8 begins with a fortepiano:
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