octave

octave [äk′tiv, äk′tāv΄]

n.

[OFr < L octava, fem. of octavus, eighth < octo,EIGHT]

1.

a) the eighth day following a church festival, counting the festival day as the first

b) the entire period between the festival and this day

2. a group of eight lines of verse; specif., the first eight lines of a Petrarchan sonnet

3. any group of eight

4. Fencing a position of thrust or parry in which the hand is rotated with the palm up

5. Music

a) the eighth tone of an ascending or descending diatonic scale, or a tone seven degrees above or below a given tone in such a scale

b) the interval of seven diatonic degrees between a tone and either of its octaves

c) the series of tones contained within this interval, or the keys of an instrument producing such a series

d) a tone and either of its octaves sounded together

e) an organ stop producing tones an octave above those ordinarily produced by the keys struck

adj.

1. consisting of eight, or an octave

2. Music producing tones an octave higher [an octave key]

octaval [äk tā′vəl, āk′tə vəl]

adj.