FORTISSIMO
fortissimo
(adjective) (chiefly a direction or description in music) very loud and strong
fortissimo, very loudly
(adverb) a direction in music; to be played very loudly
fortissimo
(noun) a musical composition or musical passage to be performed very loudly
Source: WordNet® 3.1
Etymology
Adverb
fortissimo (not comparable)
(music) Indicating that the piece is played very loud.
Noun
fortissimo (plural fortissimos or fortissimi)
(music) The dynamic sign indicating that the piece should be played fortissimo. Abbreviation: ff.
Source: Wiktionary
For*tis"si*mo ( or ), adv. Etym: [It., superl. of forte, adv. See
Forte, adv.] (Mus.)
Definition: Very loud; with the utmost strength or loudness.
Source: Webster’s Unabridged Dictionary 1913 Edition