FORTISSIMO Scrabble 15 Words With Friends 16 Definition adverb a direction in music. — synonyms: very_loudly adjective (chiefly a direction or description in music) very loud and strong. noun a musical composition or musical passage to be performed very loudly. See all 166 words you can make from FORTISSIMO → 10-letter words Words starting with F Words ending with O ← Unscramble different letters