Literal meaning of the word “Zakat” is cleansing and growth. In keeping with these qualities, Allah has prescribed Zakat as an obligatory charity, as a duty to Allah, upon every wealthy individual. Wealthy individual is defined as one who is in possession of a minimum amount of wealth called Nisab for an entire year. This charity is prescribed in order to cleanse the individual’s wealth, heart, and by extension the society in general, of the baser characteristics of miserliness, selfishness, greed, and materialism and replace them with higher qualities of generosity, love and care, and mutual help.
Various scholars have defined it more or less in this manner. They have also developed further definition of the amount that constitutes Nisab, categories of wealth, the rate of Zakat that applies to each category of wealth, and the rules of eligibility for receiving assistance from Zakat.