In physics, power is the rate of doing work, the amount of energy transferred per unit time. Having no direction, it is a scalar quantity. In the International System of Units, the unit of power is the joule per second (J/s), known as the watt in honour of James Watt, the eighteenth-century developer of the steam engine condenser.
Biblical context. The Biblical baby name Jacinth is Greek/ Latin in origin and it's meaning is reddish-blue or deep purple color. Jacinth is the name of a flower and precious stone of this color. The Hebrew word used for Jacinth in the Bible is leshem, and the Greek word is hyacinth.
Thus jazaa' (Ø¬Ø²Ø§Ø¡) can either mean reward OR punishment. So :JazakAllah can may either mean may Allah reward you or may Allah punish you, while. JazakAllah Khair means ... may Allah reward you with the Best / Good, So the correct way is to say Jazakallah khair & not just JazakAllah.