1. ottava - Noun
2. ottava - Adverb
ottava (not comparable)
(music) One octave higher; as a marking, typically abbreviated 8va.
ottava (plural ottavas)
(poetry) Ottava rima.
Sometimes 8va is used to tell the musician to play a passage an octave lower (when placed under rather than over the staff), though the similar notation 8vb (ottava bassa or ottava sotta) is also used. Source: Internet
It is used in sonnets, in ottava rima, and in many other types of poetry. Source: Internet