noun
(music) An interval of twelve semitones spanning eight degrees of the diatonic scale, representing a doubling or halving in pitch frequency.
(music) The pitch an octave higher than a given pitch.
(music) A coupler on an organ which allows the organist to sound the note an octave above the note of the key pressed (cf sub-octave)
(poetry) A poetic stanza consisting of eight lines; usually used as one part of a sonnet.
(fencing) The eighth defensive position, with the sword hand held at waist height, and the tip of the sword out straight at knee level.
(Christianity) The day that is one week after a feast day in the Latin rite of the Catholic Church.
(Christianity) An eight-day period beginning on a feast day in the Latin rite of the Catholic Church.
A small cask of wine, one eighth of a pipe.
(mathematics, obsolete) An octonion.
(signal processing) Any of a number of coherent-noise functions of differing frequency that are added together to form Perlin noise.
(astrology) The subjective vibration of a planet.
verb
Alternative form of octavate.
adjective
(obsolete) Consisting of eight; eight in number.