of or relating to the octave commencing on the G lying an octave above the treble clef
noun
3. in altissimo
Word origin
Italian, literally: highest
altissimo in American English
(ælˈtɪsəˌmou, Italian ɑːlˈtissiˌmɔ)
Music
adjective
1.
very high
noun
2. See in altissimo
Word origin
[1810–20; ‹ It: lit., highest, equiv. to alt(o) high + -issimo superl. suffix]This word is first recorded in the period 1810–20. Other words that entered Englishat around the same time include: cleavage, nihilism, rationalize, technique, zombie