Meaning of Tetrachord in Urdu

tetrachord - موسیقی کی تھیوری میں

In music theory, traditionally, a tetrachord (Greek: τετράχορδoν, Latin: tetrachordum) is a series of four notes ("chords", from the Greek chordon, "string" or "note") separated by three smaller intervals that span the interval of a perfect fourth, a 4:3 frequency proportion.