Mesocycle
As far as STS is concerned a mesocycle equals one month. STS is divided into three mesocycles, each lasting one month.
mesocycle #1 (discs 1-12) - focus is on endurance
mesocycle #2 (discs 13-24) - focus is on hypertrophy
mesocycle #3 (discs 25-36) - focus is on Strength