Octave (noun)

1. A series of eight musical notes, having a specified interval between the first and last notes.
2. A range of eight notes in a musical scale.

Origin:

From latin octava, feminine form of octavus "eighth", from octo "eight".

Examples:

1. The octave is an important interval in Western music theory.
2. The singer was able to hit high notes that spanned an entire octave.
3. The piano has a range of several octaves.
4. The octave in the melody was achieved by playing the same notes at a higher pitch.
5. The octave was used to harmonize the chords in the song.